Dragonology. Finding the maximum base clock speed

We study overclocking the Phenom II X4 940 on different motherboards and evaluate the increase in modern games

AMD, simultaneously with the release of Phenom II processors, also updated its gaming platform, which was codenamed Dragon. It should be noted that we have already examined the components of the platform individually in detail (thus, we have already comprehensively studied the chipsets of the 7th family, as well as video cards of the Radeon HD4800 family, and we have also already tested the currently most productive processor in new line: Phenom II X4 940). Since all these components, in comparison with their own competitors in terms of functionality and in tests, invariably turned out to be very attractive, it is logical to assume that the merger will no longer serve the purpose of “pulling out” a less successful component by including it in conjunction with more successful ones, but, on the contrary, will serve to add up the advantages. And indeed, the Dragon platform has every chance to succeed, which is important in a crisis, and due to its initially affordable prices.

However, in this material we will leave aside economic issues and cries of “look: this is all possible for less than $1000 for a whole computer,” and will deal exclusively with technical issues relating to the platform as a whole. Let's see how things are going with overclocking the Phenom II on different boards, because it is in the context of a gaming platform that frequency manipulation itself is perhaps most relevant (if the PC is busy with serious calculations, then let it work for at least an hour, at least a day, just to consistently provided results, and if necessary significantly faster, it is natural to think about purchasing a multiprocessor workstation or optimizing the calculations themselves). And then we will find out from a purely practical point of view what kind of increase in modern games comes from non-extreme overclocking (that is, feasible in practice without much effort and additional investment).

Brief theory

As you know, the first Phenom II models are installed on boards with Socket AM2+ connector, but since they have a declared TDP of 125 W, it is logical to consider boards that have voltage regulators of the appropriate power. This, by the way, does not mean that owners of inexpensive motherboards who are not striving for records, but also want to upgrade their computer in the future by installing a processor from the Phenom II family, will be deprived of the opportunity to upgrade, since most of the models being prepared in the future will have a TDP = 95 W, and for Assemblers of particularly compact systems are promised models with 65 and even 45 W maximum (theoretical) heat dissipation. But there are also many boards with support for TDP=125 W and higher, and thanks to their sufficient time on the market, they are affordable and are available for sale almost everywhere. Of the 7th family chipsets for gaming PCs, the most interesting are the 790GX and 790FX, which have CrossFire support and rich peripheral functionality. For the test, we simply took those that were available in our laboratory.

ASUS M3A79-T Deluxe (BIOS 0602 dated 11/11/2008)
Foxconn A7DA-S (BIOS P06 dated 12/15/2008)
Foxconn A79A-S (BIOS P06 from 01/13/2009)
Gigabyte MA790GP-DS4H (BIOS F3M)
ASRock AOD790GX/128M (BIOS 1.3 from 12/15/2008)

By the way, most boards based on the mentioned chipsets are even equipped with power circuits that are redundant for the Phenom II. After all, they were designed taking into account the installation and overclocking of older models from the Phenom line, and for example, the first revision of the Phenom 9950 had a TDP of 140 W. At the same time, the declared 125 W for the older Phenom II, apparently, is more of a reinsurance (after all, for Core i7 processors this value is 130 W, so there was no reason to set it even less, and truncation of this parameter means a more stringent selection, which negatively affects the cost and reduces the volume of supplies of chips that were already in short supply at first). In fact, the Phenom II heats up very moderately, we already had the opportunity to verify this by testing at standard frequencies, it remains to check what the situation will be during overclocking.

All boards that had older BIOS versions started correctly when installing Phenom II (frequency, multipliers, and voltage were determined correctly), but then, of course, we flashed the BIOS (from Windows) in order to test in the latest version . This is encouraging, considering that it is not uncommon for system boards with old BIOS to be sold on sale; in this case, the user does not have to look for a compatible processor for flashing or contact service.

Even non-extreme overclocking, as a rule, involves increasing the core supply voltage. The specification for the current stepping (C2) shows an operating voltage range of 0.825-1.5 V, and for overclocking with air cooling AMD does not recommend setting it higher than 1.55 V. But since even the 940 model is characterized by standard values not higher than 1, 35 V, there remains a very substantial margin for a completely safe increase.

The maximum temperature of the processor case, which is not recommended to be exceeded, is 62 degrees. We used the Zalman CNPS9700 AM2 we had on hand as a cooler. The cooler is relatively old, purchased several years ago and was not a new product even then, but in itself is quite common and effective. In addition, we do not plan to set records, that is, we did what most ordinary users do: if it is possible to keep the existing cooler without compromising the result, then why not? And when you want, for example, greater acoustic comfort or cooling reserves (for the summer), then it won’t be at all expensive to spend money on some fashionable Thermalright or Xigmatek. Of course, for those who are choosing components for a new computer with an eye toward overclocking, it makes sense to spend a little time choosing a cooler more carefully.

As for the power supply, its choice is determined by the video card planned for installation. Since we will be overclocking the senior processor in the line, it will quite naturally have to be assisted by the most powerful ATI Radeon HD4870 X2 video card. Accordingly, we had to take a branded unit with a power of 750 W (Seasonic M12D-750).

Overclocking

Although the Phenom II X4 940 has an unlocked multiplier, we first overclocked it with a fixed multiplier by increasing the reference frequency.

			Supply voltage, V	Reference frequency, MHz
ASUS M3A79-T Deluxe	3825 (x15)	2295 (x9)	1,52	255
Foxconn A7DA-S	3810 (x15)	2286 (x9)	1,52	254
Foxconn A79A-S	3825 (x15)	2295 (x9)	1,52	255
Gigabyte MA790GP-DS4H	3840 (x15)	2304 (x9)	1,52	256
ASRock AOD790GX/128M	3855 (x15)	2313 (x9)	1,52	257

And just from these results it becomes clear that choosing a board for successful overclocking of the Phenom II is a much less important task than for the Phenom. No matter how strange this expression may be in itself, even the ability to increase the frequency to 3800 MHz, demonstrated by our sample, is impressive, and this, as you can easily see from reports on overclocking resources, is by no means the limit for the Phenom II. The explanation for this suggests itself primarily in the truly significantly reduced need for power supply. After all, by the way, there are no far-fetched complaints about the power consumption of Phenom processors (revision B3) when operating at standard frequencies, but after overclocking, the board is really required to produce a fairly large current (in tests and programs with a high load on the processor). And maintaining power supply stability under such conditions is a very “delicate” matter; at a minimum, in order for the parameters not to float, it is necessary to reliably cool the stabilizer; design features also appear, hence the differences in overclocking success on different boards.

As an illustration of the moderate consumption of the Phenom II even when overclocked, the result of an inexpensive ASRock board, which does not have radiators on field-effect transistors, but formally turned out to be the leader in this test (practically a difference of 2-3 MHz in the reference frequency, of course, can be attributed to the characteristics of specific samples). At the same time, on the other boards that had heatsinks for the power stabilizer, the temperature of these heatsinks did not exceed the ambient temperature, while the field-effect transistors and coils on the ASRock AOD790GX/128M were still heated up very sensitively, and we would not recommend placing this board in a cramped environment. frame. In short, in this matter, everyone chooses for themselves whether it is worth paying extra for additional reliability or simply placing the fan on the rear wall of the case (choose a suitable processor fan with the ability to blow over the stabilizer area, etc.). Overclocking is a creative matter. The main thing is that the processor itself has become much more “friendly” to overclockers.

Since lowering the multiplier for the processor-integrated north bridge (CPU NB), for those boards for which such a setting is supported, did not further improve the result of overclocking the computing cores, we left this multiplier at the original level (x9). By the way, the relatively low default multiplier will play into the hands of owners of boards whose BIOS does not have the corresponding adjustment. At the same time, increasing the frequency of the CPU NB in itself is justified, since, along with overclocking the computing cores, it affects overall performance, especially in applications with intensive memory load.

Now let's see what we got in overclocking using multipliers.

	Core frequency (multiplier), MHz	CPU NB frequency (multiplier), MHz	Supply voltage, V	Reference frequency, MHz
ASUS M3A79-T Deluxe	3838 (x19)	2222 (x11)	1,52	202
Foxconn A7DA-S	3838 (x19)	1816 (x8)	1,52	202
Foxconn A79A-S	3857 (x19)	1824 (x8)	1,52	203
Gigabyte MA790GP-DS4H	3876 (x19)	2288 (x11)	1,52	204
ASRock AOD790GX/128M	3876 (x19)	2288 (x11)	1,52	204

Almost the same result, in other words, for our particular processor instance, the overclocking provided by increasing the reference frequency on the board is not much inferior to “autonomous” overclocking using the multiplier of the processor itself. However, overclocking in the range of 3.6-3.9 GHz is typical for the first copies (got to testers, journalists, board manufacturers, etc.), in commercial lots, as already noted, it is not exotic and achieving 4.0-4.1 GHz, also without any special tricks. And for such a processor, of course, it may already be advisable to overclock the computing cores by a multiplier, but even in this case, if the board does not support adjusting the CPU NB multiplier, such as both from Foxconn, it is better to combine both approaches in order to increase the frequency of this component.

By the way, the Advanced Clock Calibration technology, which had a very significant impact on Phenom overclocking, is now integrated into the processor, which will undoubtedly please, for example, owners of early models of motherboards based on the 790FX chipset with the SB600 southbridge, which did not support this technology. Enabling ACC on boards that have this option in the BIOS does not affect the result in any way, but on some boards where the BIOS itself is not yet sufficiently optimized for the Phenom II, it causes a freeze and the settings have to be reset.

Otherwise, no inadequacies in the behavior of the boards were found with the change of processor, which was to be expected, since Phenom II, even in matters of energy saving, which usually still depend on the board, shows great independence. In testing related to performance measurements, we usually disable dynamic frequency control technologies (Cool’n’Quiet), and this was done this time as well. Moreover, after increasing the frequency and voltage, in idle mode the heating of the processor remained exactly at the same minimum level as before this manipulation. That is, even while maintaining a constant high frequency, idle processor blocks consume very little. Apparently, here we are seeing the work of the so-called AMD CoolCore technology: dynamic shutdown of unused processor modules, otherwise there is simply nothing to explain the ability of the processor to cool down to actual ambient temperature during idle time. This technology works autonomously and does not require driver installation or inclusion in the BIOS. But in addition to all this, the processor also supports the new version of Cool’n’Quiet 3.0, which expands the idle frequency reduction range to 800 MHz, and the upcoming version of AMD OverDrive promises a combination of dynamic overclocking and frequency reduction relative to the nominal value, depending on the load.

As for operation under load, here too the heating did not exceed 52 degrees, however, the board had to maintain increased (perceptible by ear) speeds of our cooler, but this is not so critical in games (because the video card is not silent, and, most importantly, attention doesn’t switch to such trifles), so old Zalman will still serve us. However, apparently, those maximalists who, even when overclocking under load, want to get a quiet computer, will not necessarily have to use liquid cooling. As already noted, the progress of air coolers also does not stand still, there is a choice, the main thing is that extreme performance is not required from the cooling system, at least while maintaining the voltage within the recommended limits. By the way, a further increase in voltage to 1.55 V did not lead to an expansion of the frequency potential noted in the tables above, and a decrease to 1.50 V also made it possible to play all the games used as tests, but when testing stability, for example, AMD OverDrive detected errors, so for reliability, 1.52 V was set.

Having found out what our processor is capable of from a technical point of view, let's see what this gives in practice.

Test bench configuration

motherboard: Gigabyte MA790GP-DS4H
memory: 2x2 GB Corsair CM2X2048-8500C5D
video card: ASUS EAH4870X2 TOP/HTDI/2G (ATI Radeon HD 4870 X2, 1x2 GB GDDR5, frequencies increased to 790 MHz for the core and 915 (3660) MHz memory)
hard drive: Seagate ES2 SATA II 750 GB
cooler: Zalman CNPS9700 AM2
power supply: SeaSonic M12D SS-750 750 W

Software used and settings

Windows Vista SP1 64 bit, Catalyst 9.2, AMD OverDrive 2.1.5, AMD Fusion for Gaming Ultility 1.0
GTA IV: built-in benchmark, resolution: 1680x1050, settings: Texture Quality: high, Render Quality: high, View Distance: 52, Detail Distance: 100, Vehicle Density: 100, Shadow Density: 16
FarCry 2: benchmark included with the game, resolution: 1680x1050, two scenes Ranch (medium-sized map) and Action Scene, in the first case the “flying” of the map is simulated, in the second - active combat operations, see screenshot for settings:

Crysis Warhead: two timedemo Flythrough and Autotest (“fly-through” and “bypass” of the Cargo level), resolution: 1280x1024, all settings except Physics at the High level, Physics - Very High
Lost Planet Extreme Condition: built-in benchmark, resolution: 1440x900, all settings to maximum, DX10, AFx16
World in Conflict: built-in benchmark, resolution: 1680x1050, DX10, test run in two modes with Very High and High settings
PT Boards Knights of the Sea: demo benchmark, resolution: 1680x1050, DX10, all settings to maximum

We adhered to the principle of setting the settings in all tests to the maximum level (except for those cases when, as in Crysis Warhead, the maximum simply crashes any modern video card, and in practice cannot be used for normal gaming), anti-aliasing was disabled, but anisotropic filtering was selected in in accordance with the specified level of quality by the game itself (that is, it was not forced, but it was not disabled in the driver settings). The AMD Fusion for Gaming utility turned out to be very useful in practice, suspending some system services during the game, which on average increases the average frame rate by several percent even in a clean installation of Windows Vista, and also, apparently, eliminates some lags that occur if The OS suddenly decided to “calculate” something for itself. Moreover, we did not configure anything additional, we used the Basic profile, in both measurements, both with overclocking and at the standard frequency. As a test mode for overclocking, we also did not push everything to megahertz and fixed the core frequency at 3.8 GHz, and the CPU NB at 2 GHz.

	Phenom II X4 940
	Standard frequencies	Overclocking	Growth
Core frequency, GHz	3,0	3,8	26%
CPU NB frequency, GHz	1,8	2,4	33%
GTA IV, fps	48	60	25%
Crysis Warhead, Cargo Flythrough, fps	31,5	38,1	21%
Crysis Warhead, Cargo Autotest, fps	26,9	32,0	19%
Lost Planet Extreme Condition, Cave, fps	89	117	31%
FarCry 2, Ranch,	71/40	85/49	20%/23%
FarCry 2, Action Scene, average/minimum fps value	36/30	43/35	19%/17%
World in Conflict, Very High, average/minimum fps value	43/20	50/25	16%/25%
World in Conflict, High, average/minimum fps value	54/29	63/35	17%/21%
PT Boards: Knights of the Sea, average/minimum fps value	45/22	55/30	22%/36%

Despite the fact that everyone who participated in testing the game put a very serious load on the video card, the effect of increasing the processor frequency was evident everywhere, and in a number of tests it was close to linear. And this very advantageously characterizes the frequency scalability of Phenom II. After all, if in non-synthetic tests performance is limited by a small cache size or some other architectural limitations, then overclocking and releasing processors with higher frequencies have no prospects.

Also, in modern games it is clearly visible that the higher the load on the video card becomes (due to increasing the graphics settings), the higher the load on the processor. Moreover, for example, in World in Conflict, when switching from High to Very High, the load on the processor increases even more (and the effect of overclocking is higher), and vice versa, in FarCry 2, when changing a scene from a Ranch video card that seems to load more on the Action Scene, the load on the video card is growing no less, and it is the card, now forced to draw both the game characters and the environment full of “explosive” special effects, that turns out to be the “bottleneck”. Of course, in quotes, it’s comfortable to play in both episodes, since even the minimum level does not fall below 30 frames per second, including without overclocking the processor.

By the way, it is for this reason that if you need to reduce the load on the video card without much damage to the objectivity of testing, for example, to test a powerful processor on a video card of a lower class, you cannot simply reduce the quality level. You can disable anti-aliasing, anisotropic filtering, adjust some individual graphic settings (when they are available explicitly, for example, related to the quality of textures, but not the quality of shadow display!), at most, lower the resolution (but within moderate limits, since when lowering the resolution in games may well result in lower settings and simplified rendering, which is completely logical and justified). But, of course, it is better to select components of the same class and test them with the settings that will be used for the real game.

Speaking of trends in modern games, it is interesting to note the need for GTA IV in a quad-core processor, or rather, this game clearly does not have enough of a dual-core processor (any kind). Because, perhaps, a three-core Phenom II core will be enough to play without glitches, without losing too much in the settings, we don’t know that yet. Or rather, this is the topic of a separate material, the continuation of which is being prepared.

Returning to the topic of overclocking, we cannot help but note the obvious conclusion: in today's games, including the most high-tech ones, an unoverclocked Phenom II X4 940 is enough for comfortable gaming at high quality settings. That is, the Dragon platform in its maximalist configuration looks quite balanced. From a practical point of view, overclocking will probably be needed if there is a desire to install a second 4870 X2 or assemble some similar SLI tandem, or something based on those GPUs that are being prepared for release in the future, etc. Such configurations should help to more fully reveal the potential of the overclocked Phenom II in those games, where the increase in this testing turned out to be relatively small due to the limitation on the performance of the video system. On the other hand, simply increasing the already comfortable frame rate is not an end in itself; most likely the user of such a sophisticated video system will want to increase the resolution to 1920x1080, at least turn on anti-aliasing, and this, in turn, will primarily load the video cards. As a result, the image will be of higher quality, but the frame rate and the need for processor resources will increase slightly.

Remembering SLI, we must add that, of course, NVIDIA fans are not left without support on the AMD platform. Suffice it to say that the NVIDIA 750a/780a chipsets are the only ones that support SLI (in the second case, even 3-Way SLI) together with Hybrid Power technology, which is very useful for powerful video card tandems if you plan to do something else on such a computer besides games. Let us recall that this technology disables discrete video cards outside of games, and the image is formed by the video core integrated into the chipset, although, unfortunately, only under Windows Vista, and it is not yet clear whether this technology will be developed, that is, supported by future video cards (currently the older one that supports Hybrid Power, the GTX 280 remains; the recently released 285/290 are not in the compatibility list). We have already written about how this technology works.

conclusions

Frankly speaking, we had little doubt that the Dragon would at least demonstrate its worth in modern games, since we had already tested all components of the platform separately. What was really pleasing was the significantly increased attractiveness of the new processors for overclocking. Of course, this does not replace the standard recommendations for choosing high-quality coolers, power supplies and motherboards. But it is obvious that Phenom II does not suffer from being picky about the infrastructure; it operates stably at the achieved frequency and at the same time provides a convincing increase in games, especially those that are known for their high processor load. That being said, what more could you ask for (when it comes to the CPU as an overclocking target)?

Some conclusions based on the testing results can be drawn regarding the appetites of the current generation of games in general. As already noted, as the quality level increases, in most cases, the load on both the processor and the video card increases, so it is very important to test these components in modes that are as close as possible to real ones (at least according to in-game settings). Obviously, the times when performance at high quality settings invariably rested on the video card (no matter how powerful we took) are passing. This was natural for the first generations of video cards that support DirectX 10; the current ones clearly know how to not only “adjust” the corresponding shaders, but do it quickly. It is difficult to say how the situation in games will develop in the near future. On the one hand, there is still a lot of time left before the appearance of games for DX 11, and within the framework of DX 10, video cards do not have much room for growth. At the same time, game developers have already tried multi-core processors, and will certainly continue to develop this, which in general is already quite representative (in terms of the number of installed and especially newly purchased systems), but still not very popular resource. Accordingly, we would not be surprised if games released in the near future, on average, turn out to be even more critical to processor performance than video cards. However, we must not forget that, unlike the processor, the user has the opportunity (and sometimes the need) to load it additionally, for example, by setting a higher level of anti-aliasing or raising the resolution, with the purchase of another even wider monitor or TV. In a word, most likely, the optimal strategy when choosing a gaming PC will be to maintain a balance; significant “distortions” of the budget both in favor of strengthening the processor and video card are unlikely to justify themselves.

Overclocking AMD Phenom II 940 BE
Last Tuesday (May 12, 2009) at "Overclocker Club" A processor from AMD visited for the first time – Phenom II 940. At one time, this percentage shocked the entire overclocking world when the first information appeared that he doesn't have a coldbug! This is what allows AMD CPUs to show their phenomenal megahertz. Let me make a reservation: phenomenal for 4-core processors. Still, no one has yet managed to outdo Intel stones with NetBurst architecture. Also, processors from AMD have returned the sacred dream to the world of overclocking - to beat the percentages under liquid helium. But so far this dream has come true only for our Finnish comrades - SF3D, Sampsa, Macci, which overclocked the Phenom over 6500 MHz at a temperature -234 degrees Celsius. In Russia it is not yet possible to do this, and we are content with serial (and not factory-selected) processors that anyone can buy in a store, and “the old fashioned way” we cool them with liquid nitrogen.
This processor instance AMD Phenom II 940 Black Edition came to us from sunny St. Petersburg, where our northern comrades had already tormented him. But the difference between the Moscow bench and the St. Petersburg bench was the replacement of the thermal interface. DeDaL this time I used liquid metal which allowed us to obtain excellent results.

Test bench configuration:
processor AMD Phenom II 940 BE 0851APAW
motherboard DFI 790FX-B M2RSH ( We express our deep gratitude to DFI for the sample provided!)
RAM 2 x 1024 MB Corsair 8500 Micron D9GKX
video card Power Color HD4870 512 Mb
Chieftec 1200W power supply

Our hope and support for AMD is the DFI 790FX-B

Overclocking the new AMD processor caused a great stir among the audience OCClub-and the number of visitors pavilion A26+ didn't allow the store CUpil.ru it's normal to work on this day. By the way, everyone who came to this benchmark session received cool sets of screwdrivers from AMD :).

Jedal sharpens his glass of light

While DeDaL was preparing the test bench, we all listened to Cepreu’s story about his dream. The “atdushi” laughed, because he dreamed that in 2015 processors would be produced with a standard clock frequency of 5 GHz. It’s a pity, but Seryoga didn’t validate CPU-Z during overclocking - he relied on his memory, but it failed: when he woke up, he couldn’t remember his result.

Full AMD platform

Retro frequency on a modern CPU

Screenshot result at 6.3 GHz

And at this time DeDaL was already showing everyone his homemade “blank” (or whatever they call it in KVN) - downclocking up to 100 MHz. Well, now Sarkis can retire with a clear conscience - there were 8 GHz, now there are 100 MHz.
Jokes aside, the glass filled with nitrogen, and the numbers in the Frequency CPU-Z column quickly ran towards the coveted figure - 6 GHz. As a result, the result exceeded the wildest expectations: the maximum validated frequency was 6200 MHz, and some lucky people even managed to photograph the CPU-Z image and 6300 MHz.

CPU-Z - maximum validation

You don't have to worry about temperature

We are looking for the best core and ftxing the maximum frequency

Super Pi 1M's best run is truly impressive

Meanwhile, DeDaL has already begun to storm Super Pi 1M. The result was 11.297 seconds HWBot

Such a high result was achieved thanks to good overclocking NB Frequency up to 4200 MHz, which is very good!
Let us remind you that these indicators were achieved on a production sample of the processor! According to our personal statistics, out of 5 processors, 2 turned out to be very good, capable of going far beyond 6 GHz. Overclocking statistics for the AMD Phenom II 940 show that in air these processors can operate at an average of 3.6 GHz, and quite often there are instances capable of operating at 3.8-4.0 GHz. Well, super-low cold bugs make this quad-core truly unique.
Unfortunately, the time of benchmark sessions is not flexible, and we were not able to properly engage in 3D tests, however, we do not stop working with Phenom processors and will soon be able to compare DDR3 models with the DDR2 generation both in synthetic 3D benchmarks and in real ones gaming applications.

In the meantime, a few screenshots:

Screenshot of the result 11.297 sec. in Super Pi 1M

Of course, our readers know everything about overclocking. In fact, many CPU and GPU reviews wouldn't be complete without looking at overclocking potential.

If you consider yourself an enthusiast, forgive us a little basic information - we'll get into the technical details soon.

What is overclocking? At its core, the term is used to describe a component that operates at higher speeds than its specifications in order to increase performance. You can overclock various computer components, including the processor, memory and video card. And the level of overclocking can be completely different, from a simple increase in performance for inexpensive components to an increase in performance to an exorbitant level that is normally unattainable for products sold in retail.

In this guide, we'll focus on overclocking modern AMD processors to get the best performance possible given the cooling solution you choose.

Choosing the right components

The level of overclocking success depends very much on the system components. To begin with, you will need a processor with good overclocking potential, capable of operating at higher frequencies than the manufacturer normally specifies. AMD today sells several processors that have fairly good overclocking potential, with the "Black Edition" line of processors directly aimed at enthusiasts and overclockers due to the unlocked multiplier. We tested four processors from different families of the company to illustrate the process of overclocking each of them.

To overclock a processor, it is important that other components are also selected with this task in mind. Choosing a motherboard with an overclocking-friendly BIOS is quite critical.

We took a pair of Asus M3A78-T motherboards (790GX + 750SB), which not only provide a fairly large set of functions in the BIOS, including support for Advanced Clock Calibration (ACC), but also work perfectly with the AMD OverDrive utility, which is important for squeezing the most out of Phenom processors.

Choosing the right memory is also important if you want to achieve maximum performance after overclocking. Where possible, we recommend installing high-performance DDR2 memory that is capable of operating at frequencies above 1066 MHz on AM2+ motherboards with 45nm or 65nm Phenom processors that support DDR2-1066.

During overclocking, frequencies and voltages increase, which leads to increased heat generation. Therefore, it is better if your system uses a proprietary power supply that provides stable voltage levels and sufficient current to cope with the increased demands of an overclocked computer. A weak or outdated power supply, loaded to capacity, can ruin all the efforts of an overclocker.

Increasing frequencies, voltages and power consumption will, of course, lead to increased heat dissipation levels, so cooling the processor and case also greatly influences the overclocking results. We didn't want to achieve any overclocking or performance records with this article, so we took rather modest coolers priced at $20-25.

This guide is intended to help those users who are less experienced with overclocking processors, so that they can enjoy the performance benefits of overclocking their Phenom II, Phenom or Athlon X2. Let's hope that our advice will help novice overclockers in this difficult but interesting task.

Terminology

Various terms that often mean the same thing can confuse or even frighten the uninitiated user. So before we jump straight into the step-by-step guide, we'll cover some of the most common terms associated with overclocking.

Clock speeds

CPU frequency(CPU speed, CPU frequency, CPU clock speed): The frequency at which a computer's central processing unit (CPU) executes instructions (for example, 3000 MHz or 3.0 GHz). It is this frequency that we plan to increase in order to get a performance boost.

HyperTransport channel frequency: frequency of the interface between the CPU and the northbridge (for example, 1000, 1800 or 2000 MHz). Typically the frequency is equal to (but should not exceed) the northbridge frequency.

Northbridge frequency: frequency of the northbridge chip (for example, 1800 or 2000 MHz). For AM2+ processors, increasing the northbridge frequency will lead to increased memory controller performance and L3 frequency. The frequency must be no lower than the HyperTransport channel, but it can be increased significantly higher.

Memory frequency(DRAM frequency and memory speed): The frequency, measured in megahertz (MHz), at which the memory bus operates. This may include either a physical frequency, such as 200, 333, 400, and 533 MHz, or an effective frequency, such as DDR2-400, DDR2-667, DDR2-800, or DDR2-1066.

Base or reference frequency: By default it is 200 MHz. As can be seen from AM2+ processors, other frequencies are calculated from the base using multipliers and sometimes dividers.

Frequency calculation

Before we get into the frequency calculations, it's worth mentioning that most of our guide covers overclocking AM2+ processors such as the Phenom II, Phenom, or other K10-based Athlon 7xxx models. But we also wanted to cover the early AM2 Athlon X2 processors based on the K8 core, such as the 4xxx, 5xxx and 6xxx lines. Overclocking K8 processors has some differences, which we will mention below in our article.

Below are the basic formulas for calculating the above-mentioned frequencies of AM2+ processors.

CPU clock speed = base frequency * CPU multiplier;
northbridge frequency = base frequency * northbridge multiplier;
HyperTransport channel frequency = base frequency * HyperTransport multiplier;
memory frequency = base frequency * memory multiplier.

If we want to overclock the processor (increase its clock frequency), then we need to either increase the base frequency or increase the CPU multiplier. Let's take an example: the Phenom II X4 940 processor runs with a base frequency of 200 MHz and a CPU multiplier of 15x, which gives a CPU clock speed of 3000 MHz (200 * 15 = 3000).

We can overclock this processor to 3300 MHz by increasing the multiplier to 16.5 (200 * 16.5 = 3300) or raising the base frequency to 220 (220 * 15 = 3300).

But it should be remembered that the other frequencies listed above also depend on the base frequency, so raising it to 220 MHz will also increase (overclock) the frequencies of the north bridge, the HyperTransport channel, as well as the memory frequency. On the contrary, simply increasing the CPU multiplier will only increase the CPU clock speed of AM2+ processors. Below we'll look at simple multiplier overclocking using AMD's OverDrive utility, and then head into the BIOS for more complex base clock overclocking.

Depending on the motherboard manufacturer, BIOS options for processor and northbridge frequencies sometimes use not just a multiplier, but a ratio of FID (Frequency ID) and DID (Divisor ID). In this case, the formulas will be as follows.

CPU clock speed = base frequency * FID (multiplier)/DID (divisor);
Northbridge frequency = base frequency * NB FID (multiplier)/NB DID (divisor).

Keeping the DID at 1 will take you to the simple multiplier formula we discussed above, meaning you can increase CPU multipliers in 0.5 increments: 8.5, 9, 9.5, 10, etc. But if you set the DID to 2 or 4, you can increase the multiplier in smaller increments. To complicate matters, the values may be specified as frequencies, such as 1800 MHz, or as multipliers, such as 9, and you may have to enter hexadecimal numbers. In any case, refer to your motherboard manual or look online for hexadecimal values to indicate the different CPU and Northbridge FIDs.

There are other exceptions, for example, it may not be possible to set multipliers. Thus, in some cases, the memory frequency is set directly in the BIOS: DDR2-400, DDR2-533, DDR2-800 or DDR2-1066 instead of selecting a memory multiplier or divider. In addition, the frequencies of the northbridge and HyperTransport channel can also be set directly, and not through a multiplier. In general, we don't recommend worrying too much about these differences, but we recommend returning to this part of the article if the need arises.

Test hardware and BIOS settings

Processors

AMD Phenom II X4 940 Black Edition (45 nm, Quad-Core, Deneb, AM2+)
AMD Phenom X4 9950 Black Edition (65 nm, Quad-Core, Agena, AM2+)
AMD Athlon X2 7750 Black Edition (65 nm, Dual-Core, Kuma, AM2+)
AMD Athlon 64 X2 5400+ Black Edition (65 nm, Dual Core, Brisbane, AM2)

Memory

4 GB (2*2 GB) Patriot PC2-6400 (4-4-4-12)
4 GB (2*2 GB) G.Skill Pi Black PC2-6400 (4-4-4-12)

Video cards

AMD Radeon HD 4870 X2
AMD Radeon HD 4850

Cooler

Arctic Cooling Freezer 64 Pro
Xigmatek HDT-S963

Motherboard

Asus M3A78-T (790GX+750SB)

power unit

Antec NeoPower 650 W
Antec True Power Trio 650W

Useful utilities.

AMD OverDrive: overclocking utility;
CPU-Z: system information utility;
Prime95: stability test;
Memtest86: memory test (bootable CD).

Hardware monitoring: Hardware Monitor, Core Temp, Asus Probe II, other utilities included with the motherboard.

Performance testing: W Prime, Super Pi Mod, Cinebench, 3DMark 2006 CPU test, 3DMark Vantage CPU test

Manually configure Memory Timings;
Windows power plan: High Performance.

Remember that you are exceeding the manufacturer's specifications. Overclocking is done at your own risk. Most hardware manufacturers, including AMD, do not provide a warranty against damage caused by overclocking, even if you use AMD's utility. THG.ru or the author are not responsible for damage that may occur during overclocking.

Introducing AMD OverDrive

AMD OverDrive is a powerful all-in-one overclocking, monitoring and testing utility designed for motherboards based on the AMD 700 series chipset. Many overclockers do not like to use a software utility under the operating system, so they prefer to change the values directly in the BIOS. I also usually avoid utilities that come with motherboards. But after testing the latest versions of the AMD OverDrive utility on our systems, it became clear that the utility is quite valuable.

We'll start by taking a look at the AMD OverDrive utility menu, highlighting interesting features as well as unlocking the advanced features we'll need. After launching the OverDrive utility, you are greeted with a warning message, clearly stating that you are using the utility at your own risk.

When you agree, pressing the "OK" key will take you to the "Basic System Information" tab, which displays information about the CPU and memory.

The "Diagram" tab displays a chipset diagram. If you click on a component, more detailed information about it will be displayed.

The "Status Monitor" tab is very useful during overclocking, as it allows you to monitor the processor clock speed, multiplier, voltage, temperature and load level.

If you click on the "Performance Control" tab in the "Novice" mode, you will get a simple engine that allows you to change the PCI Express (PCIe) frequency.

To unlock advanced frequency settings, go to the "Preference/Settings" tab and select "Advanced Mode".

After selecting the "Advanced" mode, the "Novice" tab was replaced by the "Clock/Voltage" tab for overclocking.

The "Memory" tab displays a lot of information about memory and allows you to configure delays.

There's even a built-in test to quickly evaluate performance and compare it with previous values.

The utility also contains tests that load the system to check the stability of operation.

The last tab "Auto Clock" allows you to perform automatic overclocking. It takes a lot of time, and all the excitement is lost, so we didn’t experiment with this function.

Now that you're familiar with AMD's OverDrive utility and have set it to Advanced mode, let's move on to overclocking.

Overclocking via multiplier

With the 790GX motherboard and Black Edition processors we used, overclocking using AMD's OverDrive utility is fairly easy. If your processor is not a Black Edition processor, you will not be able to increase the multiplier.

Let's take a look at the stock operating mode of our Phenom II X4 940 processor. The motherboard base frequency varies from 200.5 to 200.6 MHz for our system, which gives a core frequency between 3007 and 3008 MHz.

It is useful to run some performance tests at the standard clock frequency, so that you can then compare the results of an overclocked system with them (you can use the tests and utilities we suggested above). Performance tests allow you to measure performance gains and losses after changing settings.

To overclock a Black Edition processor, check the "Select All Cores" checkbox on the "Clock/Voltage" tab, then start increasing the CPU multiplier in small steps. By the way, if you don’t check this box, you can overclock the processor cores individually. As you overclock, be sure to keep an eye on temperatures and constantly run stability tests. In addition, we recommend making notes regarding each change where you describe the results.

Since we were expecting a solid boost from our Deneb processor, we skipped the 15.5x multiplier and went straight to the 16x multiplier, which gave the CPU core clock at 3200 MHz. With a base frequency of 200 MHz, each increase in the multiplier by 1 gives an increase in clock frequency of 200 MHz, and an increase in the multiplier by 0.5 - 100 MHz, respectively. We performed stress tests after overclocking using the AOD stability test and the Small FFT Prime95 test.

After running Prime 95 stress tests for 15 minutes without a single error, we decided to further increase the multiplier. Accordingly, the next multiplier of 16.5 gave a frequency of 3300 MHz. And at this core frequency, our Phenom II passed through stability tests without any problems.

A multiplier of 17 gives a clock speed of 3400 MHz, and again stability tests were completed without a single error.

At 3.5 GHz (17.5*200) we successfully completed a one-hour stability test under AOD, but after about eight minutes in the heavier Prime95 application we got a blue screen and the system rebooted. We were able to run all of our performance tests on these settings without crashing, but we still wanted our system to get through the 30-60 minute Prime95 test without crashing. Therefore, the maximum overclocking level of our processor at a nominal voltage of 1.35 V is between 3.4 and 3.5 GHz. If you don't want to raise the tension, then you can stop there. Or you can try to find the maximum stable CPU frequency at a given voltage by increasing the base frequency in one megahertz increments, which for a multiplier of 17 would give 17 MHz at each increment.

If you don’t mind raising the voltage, then it is better to do this in small increments of 0.025-0.05 V, while you need to monitor the temperatures. Our CPU temperatures remained low, and we began to gradually increase the CPU voltage, with a small increase to 1.375 V resulting in Prime95 tests running at 3.5 GHz completely stable.

Stable operation with a multiplier of 18 at 3.6 GHz required a voltage of 1,400 V. To maintain stability at 3.7 GHz, a voltage of 1.4875 V was required, which is more than the AOD allows to set by default. Not every system will be able to provide sufficient cooling at this voltage. To increase the default AOD limit, you should edit the AOD .xml parameters file in Notepad, increasing the limit to 1.55 V.

We had to raise the voltage to 1,500 V to get the system to work stably in the 3.8 GHz tests with a multiplier of 18, but even raising it to 1.55 V did not lead to stable operation of the Prime95 stress test. The core temperature during Prime95 tests was somewhere in the region of 55 degrees Celsius, meaning we hardly needed better cooling.

We rolled back to the 3.7 GHz overclock, and the Prime95 test ran successfully for an hour, meaning system stability was verified. We then started increasing the base frequency in 1 MHz increments, with the maximum overclock level being 3765 MHz (203*18.5).

It is important to remember that the frequencies that can be obtained through overclocking, as well as the voltage values for this, change from one processor sample to another, so in your case everything may be different. It is important to increase frequencies and voltages in small increments while performing stability tests and monitoring temperatures throughout the process. With these CPU models, increasing the voltage does not always help, and processors may even become unstable if the voltage is increased too much. Sometimes for better overclocking it is enough to simply strengthen the cooling system. For optimal results, we recommend keeping the CPU core temperature under load below 50 degrees Celsius.

Although we were unable to increase the processor frequency above 3765 MHz, there are still ways to further improve system performance. Increasing the frequency of the northbridge, for example, can have a significant impact on application performance, since it increases the speed of the memory controller and L3 cache. The northbridge multiplier cannot be changed from the AOD utility, but this can be done in the BIOS.

The only way to increase the northbridge clock speed under AOD without rebooting is to experiment with the CPU clock speed with a low multiplier and a high base frequency. However, this will increase both the HyperTransport speed and the memory frequency. We'll look at this issue in more detail in our guide, but for now let me present the results of overclocking three other Black Edition processors.

The other two AM2+ processors are overclocked in exactly the same way as the Phenom II, with the exception of one more step - enabling Advanced Clock Calibration (ACC). The ACC function is only available on motherboards with AMD SB750 Southbridge, such as our ASUS model with the 790GX chipset. The ACC feature can be enabled in both AOD and BIOS, but both require a reboot.

For 45nm Phenom II processors, it is better to disable ACC, since AMD states that this feature is already present in the Phenom II die. But with 65nm K10 Phenom and Athlon processors, it is better to set ACC to Auto, +2% or +4%, which can increase the maximum achievable processor frequency.

Standard frequencies.

Maximum multiplier

Maximum overclocking

The screenshots above show the overclocking of our Phenom X4 9950 at the stock frequency of 2.6 GHz with a 13x multiplier and a processor voltage of 1.25 V. The memory frequency is crossed out because it was set to DDR2-1066, and not to the DDR2-800 mode that we used for overclocking. The multiplier was increased to 15x, giving a 400 MHz overclock at stock voltage. The voltage was increased to 1.45V, then we tried ACC settings on Auto, +2%, and +4%, but the Prime95 could only last 12-15 minutes. Interestingly, with ACC in Auto mode, a 16.5x multiplier and a voltage of 1.425V, we were able to increase the base frequency to 208MHz, which gave a higher stable overclock.

Standard frequencies

Maximum overclocking without increasing voltage

Maximum overclocking without using ACC

Maximum overclocking

Our Athlon X2 7750 operates at a standard frequency of 2700 MHz and a voltage of 1.325 V. Without increasing the voltage, we were able to increase the multiplier to 16x, which gave a stable operating frequency of 3200 MHz. The system was also stable at 3300 MHz when we increased the voltage slightly to 1.35 V. With ACC disabled, we increased the processor voltage to 1.45 V in 0.025 V increments, but the system was not able to operate stably at the 17x multiplier. It crashed even before stress testing. Setting ACC for all cores to +2% allowed Prime95 to run for an hour at 1.425 V. The processor did not respond well to voltages above 1.425 V, so we were able to get a maximum stable clock of 3417 MHz.

The benefits of enabling ACC, as well as the results of overclocking in general, vary significantly from one processor to another. However, it’s still nice to have such an option at your disposal, and you can spend time fine-tuning the overclocking of each core. We didn't see any significant overclocking gains from enabling ACC on either processor, but we still recommend checking out our 790GX review where we took a closer look at ACC and where it made a more significant impact on the Phenom X4 9850's overclocking potential.

BIOS options

Our Asus M3A78-T motherboard was flashed with the latest BIOS version, which contains support for the new CPUs and also provides the best chance of successful overclocking.

To begin, you need to enter the motherboard BIOS (usually done by pressing the "Delete" key during the POST boot screen). Check your motherboard's manual to see how you can clear the CMOS (usually using a jumper) if the system fails the POST boot test. Remember that if this happens, all previously made changes such as time/date, GPU off, boot order, etc. will be lost. If you're new to BIOS setup, pay close attention to the changes you make and write down the initial settings if you can't remember them later.

Simply navigating the BIOS menu is completely safe, so if you're new to overclocking, don't be afraid. But make sure you exit the BIOS without saving any changes you've made if you think you might accidentally mess something up. This is usually done by pressing the "Esc" key or the corresponding menu option.

Let's dive into the Asus M3A78-T BIOS as an example. BIOS menus vary from one motherboard to another (and from one manufacturer to another), so use the manual to find the appropriate options in your model's BIOS. Also, remember that the available options vary greatly depending on your motherboard model and chipset.

In the main menu (Main) you can set the time and date, and the connected drives are also displayed there. If a menu item has a blue triangle on the left, you can go to a submenu. The "System Information" item, for example, allows you to view the BIOS version and date, processor brand, frequency and amount of installed RAM.

The "Advanced" menu consists of several nested submenus. The "CPU Configuration" item displays information about the processor and contains a number of options, some of which are best disabled for overclocking.

You will probably spend most of your time in the "Advanced" menu item "JumperFree Configuration". Manual setting of important settings is ensured by switching the “AI Overclocking” item to the “Manual” mode. On other motherboards, these options will probably be located in a different menu.

Now we have access to the necessary multipliers that can be changed. Please note that in the BIOS the CPU multiplier changes in steps of 0.5, and the northbridge multiplier in steps of 1. And the HT channel frequency is indicated directly, and not through the multiplier. These options vary significantly between different motherboards; for some models they can be set via FID and DID, as we mentioned above.

In the "DRAM Timing Configuration" item you can set the memory frequency, be it DDR2-400, DDR2-533, DDR2-667, DDR2-800 or DDR2-1066, as shown in the photo. In this BIOS version you will not need to set the memory multiplier/divider. In the "DRAM Timing Mode" item you can set delays, either automatically or manually. Reducing latency can improve performance. However, if you do not have completely stable values of memory latencies at different frequencies at hand, then during overclocking it is very reasonable to increase the latencies CL, tRDC, tRP, tRAS, tRC and CR. Additionally, you can get higher memory frequencies if you increase tRFC latencies to very high values such as 127.5 or 135.

Later, all the "relaxed" delays can be returned back to squeeze out more performance. Reducing one latency per system run is time-consuming, but worth the effort to get maximum performance while maintaining stability. When your memory is operating outside of specifications, run a stability test with utilities such as Memtest86 bootable CD, as unstable memory performance can lead to data corruption, which is not desirable. With all that said, it is quite safe to give the motherboard the ability to adjust the latencies on its own (usually this will set fairly “relaxed” latencies) and focus on overclocking the CPU.

Advanced overclocking

In this case, the adjective “advanced” is not very appropriate, since, unlike the methods discussed above, we will present here overclocking through the BIOS by increasing the base frequency. The success of such an overclock depends on how well the components in your system can overclock, and to find the capabilities of each of them, we will go through them one by one. In principle, no one forces you to follow all the steps given, but finding the maximum for each component can ultimately lead to higher overclocking, since you will understand why you are running into one or another limit.

As we said above, some overclockers prefer direct overclocking through the BIOS, while others use AOD to save testing time by not having to reboot every time. The settings can then be manually entered into the BIOS and try to improve them even further. In principle, you can choose any method, since each has its own advantages and disadvantages.

Again, it would be a good idea to disable the Cool"n"Quiet and C1E, Spread Spectrum and automatic fan control systems in the BIOS, which reduce fan speed. We also turned off the "CPU Tweak" and "Virtualization" options for part of our tests, but did not find a noticeable effect on any of the processors. These features can be enabled later if required and you can check if they impact system performance or the stability of your overclock.

Finding the maximum base clock speed

Now we'll move on to the techniques that owners of non-Black Edition processors will have to follow to overclock them (they cannot increase the multiplier). Our first step is to find the maximum base frequency (bus frequency) at which the processor and motherboard can operate. You will quickly notice all the confusion in the naming of the various frequencies and multipliers, as we already mentioned above. For example, the reference clock in AOD is called "Bus Speed" in CPU-Z and "FSB Frequency" in this BIOS.

If you plan to overclock only through the BIOS, then you should lower the CPU multiplier, northbridge multiplier, HyperTransport multiplier and memory multiplier. In our BIOS, lowering the Northbridge multiplier automatically reduces the available HyperTransport channel frequencies to or below the resulting Northbridge frequency. The CPU multiplier can be left as standard and then lowered in AOD, which makes it possible to further increase the CPU frequency without rebooting.

For our Phenom X4 9950 processor, we selected an 8x multiplier in the AOD utility, since even a 300 MHz base frequency with such a multiplier will be lower than the standard CPU frequency. We then raised the base frequency from 200 MHz to 220 MHz, and then increased it in 10 MHz steps up to 260 MHz. We then moved to 5 MHz steps and increased the frequency to a maximum of 290 MHz. In principle, it is unlikely to increase this frequency to the limit of stability, so we could easily stop at 275 MHz, since it is unlikely that the northbridge will be able to operate at such a high frequency. Since we were overclocking the base clock in the AOD, we ran AOD stability tests for a few minutes to ensure the system was stable. If we did the same thing in the BIOS, simply being able to boot into Windows would probably be a good enough test, and then we'd run final stability tests at a high base clock to make sure.

Finding the maximum CPU frequency

Since we already reduced the multiplier in AOD, we know the maximum CPU multiplier and now we already know the maximum base frequency we can use. With the Black Edition processor we can experiment with any combination within these limits to find the maximum value of other frequencies, such as the northbridge frequency, the HyperTransport channel frequency and the memory frequency. For now, we will continue the overclocking tests as if the CPU multiplier was locked at 13x. We will look for the maximum CPU frequency by increasing the bus frequency by 5 MHz at a time.

Whether overclocking via BIOS or via AOD, we can always go back to the base clock of 200 MHz and set the multiplier back to 13x, which will give a stock clock speed of 2600 MHz. By the way, the north bridge multiplier will still remain 4, which gives a frequency of 800 MHz, the HyperTransport channel will operate at 800 MHz, and the memory will operate at 200 MHz (DDR2-400). We will follow the same procedure of increasing the base frequency in small increments, performing stability tests each time. If necessary, we will increase the CPU voltage until we reach the maximum CPU frequency (by enabling ACC in parallel).

Maximum performance gain

Having found the maximum CPU frequency of our AMD processors, we have taken a significant step towards increasing system performance. But processor frequency is only part of overclocking. To get maximum performance, you can work on other frequencies. If you increase the voltage of the north bridge (NB VID in AMD OverDrive), then its frequency can be increased to 2400-2600 MHz and higher, and you will increase the speed of the memory controller and L3 cache. Increasing the frequency and reducing RAM latency can also have a positive effect on performance. Even the high-end DDR2-800 memory we used can be overclocked above 1066 MHz, increasing voltage and possibly reducing latency. HyperTransport channel frequency generally does not affect performance above 2000 MHz and can easily lead to instability, but it can also be overclocked. The PCIe frequency can also be slightly overclocked to around 110 MHz, which can also provide a potential performance boost.

As all mentioned frequencies slowly rise, stability and performance tests should be carried out. Setting up different parameters is a lengthy process and may be beyond the scope of our guide. But overclocking is always interesting, especially since you will get a significant performance boost.

Conclusion

Let's hope that all our readers who want to overclock an AMD processor now have a sufficient amount of information on hand. Now you can start overclocking using the AMD OverDrive utility or other methods. Remember that the results and exact sequence of actions vary from one system to another, so you should not blindly copy our settings. Use this manual only as a guide to help you discover the potential and limitations of your system for yourself. Take your time, don't increase your pitch, monitor temperatures, perform stability tests, and increase the voltage a little if necessary. Always carefully probe the safe overclocking limit, since a sharp increase in frequency and voltage blindly is not only a wrong approach for successful overclocking, but it can also damage your hardware.

The last piece of advice: each motherboard model has its own characteristics, so it doesn’t hurt to familiarize yourself with the experiences of other owners of the same board before overclocking. Advice from experienced users and enthusiasts who have tried this motherboard model in action will help you avoid pitfalls.

Addition

We tested another copy of the AMD Phenom II X4 940 Black Edition processor, provided by the Russian representative office of AMD. It ran successfully at 3.6 GHz when we increased the supply voltage to 1.488 V (CPUZ data). It looks like 3.6 GHz is the threshold for most CPUs when air cooled. We successfully overclocked the memory controller to 2.2 GHz.

After Core 2 Duo, the requirements are always high :) But AMD captivates with its price, and in the end the choice was made.

After reading on forums, in magazines and asking people, I decided to switch to a quad-core processor without any special financial costs. The choice fell on the Phenom II X4, the junior model 810. An ASRock A770DE motherboard was purchased along with it. We needed an inexpensive ATX board with 3 pci and 2 pci-express. There wasn’t much choice :)

Test configuration

CPU AMD Phenom X4 810 (2.6 GHz, Quad-core, 4Mb L3)
M.B. Asrock A770DE
Cooler BOX is so small :)
RAM 2x2Gb TakeMS DDR2-800 CL5
HDD WD6400AAKS 640 Gb 16 Mb 7200rpm
video ASUS EN7300GT Silent 256Mb
BP CoolerMaster 460W 460-PCAP-A3
frame 4U 4710 + 120 mm exhaust fan @ 5V
OS Windows XP SP3 32 bit

Overclocking

Having read about how well the Phenom II drives, even at standard voltage, I decided to test this thesis. Also roughly estimate the power consumption of the processor. Unfortunately, I couldn’t find the specific heat dissipation of the 810th processor on the network; whoever finds out, I’ll fix it, so we’ll take the heat dissipation to be equal to TDP = 95 W.

Overclocking was carried out with the following settings:

Cool'n'Quiet - OFF
NB and HT multiplier – 8
Voltage NB - 1.2 V
Bus frequency - 270 MHz
Memory frequency – 448 MHz (892 DDR2) (1.66 multiplier)

The processor multiplier dropped to 10, so I looked at how much the processor would take, starting from almost the default frequency on the 270 MHz bus. The frequency was changed in steps of 0.5*270, i.e. 135 MHz.

At the standard voltage (1.325V), the processor reached the “peak” of 3105 MHz. Not much, some boasted almost 3.6 GHz. In this case, the estimated heat release (HT) = 113 W. Etc. according to the sign

*—calculated based on TDP

Box cooler

To be honest, I didn’t want to make a stove out of my computer in the summer, so the increase in frequency seemed rather modest. In addition, the boxed cooler can barely cope with a 1.475 V processor at maximum speed (and is very noisy at the same time).

Even at default, the cooler accelerates over 1800 rpm when encoding video - the noise becomes noticeable. Those. If you like quiet computers, I recommend either buying a normal cooler or... undervolting.

Undervolting

By analogy with overclocking, undervolting is a phenomenon in which the processor frequency and performance are often left the same, but the supply voltage is reduced. The result is a cooler processor running at the same frequency with the same performance. Intel and AMD are charging real money for these processors - Intel Q8200S, Q9400S, Q9550S, as well as AMD Phenom 705e, 905e. Let's make such a processor with our own hands;)

My processor was able to pass the S&M tests at the standard 2.6 GHz frequency at 1.15 V, resulting in a heat dissipation of about 72 W. It’s not for nothing that AMD sets a frequency of 2.5 GHz on its 65W processors.

As a result, I didn’t even have to buy a normal cooler - on the boxed one, the temperature when encoding video did not rise above 51 degrees at 1500 rpm - quiet and comfortable.

Cool'n'Quiet and performance

To be honest, I had to disable CnQ due to the drop in performance even on Windows. All kinds of flash, a couple of browsers and 800 MHz are no longer enough, and the driver for XP is clumsy. What is the reason? If it's on Windows, then I'm not going to change it yet :) I decided to look at the performance of phenoms at a reduced frequency.

To do this, the frequency was reduced by a multiplier. NB, HT and memory frequencies remained standard.

Results in Everest 5.02:

CPU test/configuration, cores x MHz	1×100	4×100	1×600	4×600	4×2600
Reading from memory, MB/s	—	629	—	3121	7186
Memory latency, ns	—	540	—	133,7	64
CPU Queen	181	—	1100	3716	16122
CPU ZLib	647	2593	—	—	68225

The results speak for themselves - back to the days of the Pentium 100 :).

The performance of the memory controller also directly depends on the frequency. So I decided to disable CnQ for now, at least until I switch to Windows 7.