Selecting an ssd controller. How to choose an SSD drive for a computer: main nuances and analysis of characteristics
Solid state drives (SSDs) have been on the market for a long time, but they have been gaining more and more popularity recently. SSD drives are quite expensive, but they greatly improve system performance due to their very high speed of reading and writing data.
Unlike conventional hard drives, instead of magnetic tracks, a new technology is used - flash memory. But in addition to the great advantage in performance, there are several more disadvantages here - these are service lines, small volume and high price. In this article we will try to figure out how to choose an SSD drive for a computer, and also look at what they are and how they differ from each other. But first you need to find out what SSD drives are.
SSD or Solid State Drive is a storage device without moving elements based on memory chips or in other words, a solid state drive.
A typical hard drive consists of a magnetic disk rotating at high speed and a head for reading and writing data. Data storage is performed by magnetizing and demagnetizing the desired cells. But working with the cell, changing the disk rotation speed, and most importantly, moving the recording head takes too much time. Therefore, the hard drive cannot be very fast.
But an SSD drive solves this problem. Here, instead of this whole complex mechanism, flash memory is used. Thanks to this, there is no longer any need to move the recording head; recording to any point on the disk is instantaneous.
But chip-based memory technology is more expensive than conventional hard drives. In addition, flash memory has one very undesirable property - a limited number of rewrites. Therefore, manufacturers have to come up with different ways of cell placement and compensation to ensure that their drives last as long as possible.
So that you can choose the right ssd drive for your computer, you first need to consider what types of drives exist.
Types of SSD drives
During the development of this technology, several types of SSD drives have appeared; they differ in size, method of connection to the computer, operating speed and method of placing memory cells.
Dimensions and connection methods
The size, method of connecting the SSD drive to the motherboard and operating speed are related to each other, because these characteristics depend specifically on the connection interface. Let's look at the most common ways to connect an SSD so that you know which ssd to choose:
- SATA- these SSD drives connect to the same interface as regular HDD drives. To be compatible with the installation space, these drives have a housing measuring 9x7x2.5 centimeters, which corresponds to the size of the HDD. Nowadays, they are used most often because they can be easily installed in any computer or laptop instead of a regular hard drive. But this option has a limitation - the maximum data transfer speed is 6 GB/second. For an HDD this is a very large figure, but some SSDs can develop even more.
- mSATA- exactly the same connection interface as SATA, and therefore the same operating speed. Only there is not such a large building here. This type of SSD is often used for laptops. The only difference between this type of disk is the size.
- PCIe- these drives look like a regular PCI card and, thanks to the use of this interface, can achieve data transfer speeds of up to 30 Gb/sec. But they can only be used in personal computers due to their size, and also cost two or even three times more than regular SATA SSDs.
- NVMe- a modification of PCIe SSD drives that provides even greater performance thanks to special optimizations, but at the moment it is only compatible with new motherboards. The case looks exactly the same as the PCIe one.
- M.2. is a smaller version of an SSD drive for PCI. It works using the same protocol and allows you to develop the same speed of data processing, but instead of a large case it is made in the form of one small board. Most modern boards already support slots of this type, but they can also be connected simply via PCI.
Methods for organizing memory cells
Based on the way SSD memory cells are organized, drives are divided into different numbers of bits that are stored in one cell. In fact, the less, the greater the rewrite resource and the speed of operation, but at the same time the higher the price. Therefore, manufacturers are trying to reduce the cost of production by increasing the amount of data in one cell. Currently there are the following types of memory:
- SLC NAND- This type of memory was developed quite a long time ago. One cell contains one bit of data. It guarantees maximum performance and up to ten thousand data overwrites, but is very expensive and therefore not released.
- MLC NAND is the next generation of flash memory, in which there are two bits per cell. The number of possible rewrites is reduced to three thousand times, and the operating speed is halved. But the price of such devices is already more or less acceptable.
- TLC NAND- in this standard, one cell already contains 3 bits of data and the rewriting resource drops to 1000. But they are even cheaper. Manufacturers have found a way out of the situation by adding various balancing controllers, which replace the failed cells with reserve ones, and also try to give the same load to all cells. A cache from SLC memory is also used. All this allows us to guarantee the operation of the SSD for up to 3 years or more.
Nowadays TLC and MLC with various optimizations are most often used.
How to choose an SSD drive?
Now that you already know what SSD drives are, let's look at how to choose an SSD drive for your computer. New users only pay attention to volume, price and size. But you also need to take into account the type of memory placement, connection method and controller manufacturer.
SSD memory capacity
The larger the size, the higher the price of the device, but at the same time, the greater the rewriting resource, because the controller has more space to redistribute the load between all cells. Most often, SSD drives come in sizes of 128, 256 GB and 1 TB. Most often, users take a 128 GB SSD for the system.
Connection method
In fact, there are only two connection methods: using the SATA interface and PCI. SATA is more common and versatile. This SSD drive can be installed in both a computer and a laptop. But if you want very high speed, it is better to choose the PCI interface.
Memory type
To find out which ssd is better to choose 2016 for your computer, you need to pay attention to the type of memory. The first type of memory, SLC, is no longer available. There are two types common in the market - MLC and TLC. The first one is more expensive, but has a recording resource of 3000 thousand times, and the speed of working with data is 50 milliseconds. Such disks can last 5-7 years with normal use, but are more expensive.
Discs using TLC memory have a write life of 1000 times, a 75 millisecond read time and a service life of about three to five years. For a home computer, it is quite possible to choose TLC memory. But if you copy large files very often, then it is better to choose MLC.
Chip manufacturer
There is one more very important parameter that is worth paying attention to. This is the manufacturer of the controller chip. On the one hand, it may seem that this does not matter, but each manufacturer has its own characteristics and disadvantages.
- SandForce- This is one of the most popular controllers. It is quite cheap and has good performance. The main feature is the use of compression when writing data to the media. But there is a drawback - when the disk is full, the recording speed drops significantly;
- Marvel- similar to SandForce, has excellent operating speed, but it no longer depends on the disk full percentage. Disadvantage - too expensive;
- Samsung- also quite popular controllers. They have support for AES encryption at the hardware level, but sometimes you can observe a decrease in speed due to problems with the garbage collection algorithm;
- Fizon- has excellent performance, a low price and the absence of any problems that would reduce speed. But there is a drawback here. It performed poorly in random write and read operations;
- Intel- better than Fizon, but much more expensive.
The main manufacturers of memory boards are Samsung, SanDisk, Intel and Toshiba. But memory boards are not that different, so the choice of board manufacturer does not matter much.
An SSD solid-state hard drive has many advantages over a standard HDD drive, the most important of which is its much higher operating speed.
Advantages of SSD drives
The advantages of solid-state drives lie in the construction of their internal structure based on memory chips, which are controlled by a special controller.
The absence of moving parts, high mechanical resistance, low noise level and no time spent reading pieces of information in different places on the disk are not a complete list of the advantages of SSD drives.
Disadvantages of SSD drives
1. Short service life. The main disadvantages of solid-state drives include their short service life, which is measured by the manufacturer in units of the number of times information is rewritten, for example, 10 thousand times. The exact number of times to rewrite depends on the type of memory. The service life of an SSD drive depends on the intensity of its use (overwriting), which with an average load ranges from 1 to 3 years.
When the media wears out, all information on the disk is lost. To monitor the “health” of the disk, there is a special program SSD Life Left, which calculates the wear rate as a percentage and warns the user about the imminent “death” of the disk in order to leave the opportunity to transfer data to another disk.
2. High cost. SSD drives are significantly more expensive than traditional HDD hard drives. Despite this, in situations where high data processing speed is required while supporting the execution of several tasks simultaneously, an SSD drive becomes a kind of “lifesaver” and is so far the only device that is capable of fulfilling such serious goals set for it.
What is an SSD drive for?
Basically, solid-state drives are used to install an operating system on it, since this can significantly increase the speed of the operating system, launching applications and processing data. The use of SSD drives for servers is very common, because such devices are capable of quickly performing thousands of simultaneous operations, while guaranteeing stable buffer storage of operational data.
It is better not to use an SSD drive as a regular disk because of their main drawback - rapid failure due to wear and tear of memory cells due to frequent rewriting. For static storage of information that changes slightly, you can use an SSD drive, but its high cost does not always allow you to purchase a large-capacity drive.
Main characteristics of SSD drives
Capacity
Netbooks and subnotebooks are usually equipped with SSD drive models with a capacity of 8 GB, sometimes 32 GB, while in regular laptops this parameter reaches 256 and 516 GB. Its cost greatly depends on the capacity of the disk.
For stable operation of the system, a memory capacity of 60-90 GB is sufficient. The most common models are those with a capacity of 128 GB.
Memory type
There are two types of memory that are used when building SSD drives: SLS and MLS.
SLS is a type of memory consisting of cells containing 1 bit of information and capable of having only two charge levels - 0 and 1. Its advantage is higher speed and durability, but its disadvantage is its high price.
MLS is a type of multi-level memory containing cells of several bits. Cells of this type are capable of being in different states of charge, which helps to increase capacity. The disadvantages of this type of memory are an increase in data access time and a decrease in service life due to a tenfold reduction in the number of rewrites compared to SLS. The service life of a disk on MLS memory on average does not exceed three years. Accordingly, devices with MLS memory are much cheaper.
Controller
The main part of an SSD drive is the controller, which determines the speed, stability, reliability and quality of the device. There are several types of controllers, among which there are six most popular.
JMicron is from the first generation, has low performance and a small amount of cache memory, but is the most affordable of all. Today it is unlikely to find this type of controller. However, the low cost caused a surge in sales at one time, and perhaps manufacturers will soon introduce new solutions for this type of device to the market.
Indilinx – good performance with a small disk thickness and memory capacities up to 512 GB.
SandForce is the most widely used controller type. Its operation is based on the principle of data compression, which is performed immediately before recording to disk. The disadvantage is the complicated operating logic of such a controller, but this disadvantage is justified by high performance and reduced memory access time. Reduced data takes up less space, which reduces the number of accesses to its cells, and therefore this technology increases the service life of the media.
Marvell is a controller type somewhat inferior to SandForce in terms of operating speed, and not as expensive.
Samsung – used in SSD drives of the same name, with fairly high operating speeds and a considerable amount of cache memory.
Intel - most often used for servers and workstations due to its reliability. The only thing that prevents these devices from becoming the controller market leader is their very low write speed.
Interface
SATA, SATA2 and SATA3 interfaces are the most common for SSD drives, providing parallel data exchange with a computer and without requiring the installation of additional software.
The PCIe interface is less common, supporting much faster data exchange with a computer, while in most cases requiring the installation of a special driver.
MTBF – number of hours between failures
This figure is indicated by the manufacturer and ranges from 1 to 2 million hours, but in reality, not a single disk will work that long due to memory wear. Therefore, you can ignore this figure.
Price
The cost of any new product that has just entered the market is generally always overpriced. Therefore, it is better not to rush, and before purchasing the latest SSD drive model, evaluate the selected model after about 3-4 months, when its price will be much more similar to the real one.
We have already talked about SSDs several times and I am more than sure that many of you know what it is, those who don’t know.
So, if you want your computer to work better and faster, then an SSD drive will help you with this. Access to data occurs almost instantly and this speeds up loading, for example, systems or launching programs. In other words, whatever you try to open will open almost instantly.
If you replace your HDD with such a device, the benefits will be noticeable to a greater extent than if we simply replaced the RAM. As I have said in many of my articles, the only drawback of these devices is that they are very expensive, so many cannot afford them.
Also, information on the service life of the SSD is considered important, since memory cells are subject to wear. To increase service life, I will tell you several methods, but this is only for solid-state drives, this practically does not apply to regular hard drives.
Purchase and operation
In this article, we will look at 5 points of operation of SSD drives, you need to know them before choosing a disk. In paragraph 6, we will look at the principle of operation, the differences between SSDs and conventional hard drives, for example, when deleting data.
Choosing a universal hard drive
Those users who want to purchase a new hard drive instead of an old one should pay attention to an interesting 500 GB SSD drive. They cost approximately 13,000 rubles, but will provide you with speed and plenty of space.
Even if we take into account that the SATA-3 interface limits the data transfer speed to 600 MB/s, then SSD drives have a speed 5 times higher than conventional hard drives. Also, solid-state drives can have a warranty of 3 years and are designed for such a volume of recorded information that would be achieved only after 10 years.
SSD Model - Transcend SSD370S has a capacity of 512 GB and costs approximately 15 thousand rubles, data access time is achieved almost immediately, and there is also optimal energy efficiency. There is a similar model - Samsung SSD850 Evo for 500 GB, price 14 thousand rubles, warranty up to 5 years.
Let's look at the performance
In order to get the most out of an SSD, you need to use PCI Express 3.0 rather than SATA, the best option would be to purchase a motherboard.
Now you can find the following models of this product: Intel SSD 750 400 GB or 1200 GB, price from 37 thousand rubles to 98 thousand rubles, a little expensive, but this is the best option. Second model - Samsung SSD 950 Pro from 256 to 512 GB, price 17-29,000 rubles. The model also has a form factor - M.2, which creates compatibility with modern computer motherboards and laptops with an M.2 slot.
The data transfer speed of such SSDs is more than 2 Gb/s; as you can see, there is a big difference compared to SATA-SSDs.
Transferring the OS to an SSD drive
If your operating system is located on an HDD, then you should think about transferring it to an SSD. After this, the performance will noticeably improve and you will notice it charmingly.
There is a utility O&O SSD Migration Kit, which helps to transfer to SSD. Of course, there are failures, so you can use software, for example, from the manufacturer. Example - Samsung Data Migration. In any case, connect the SSD to your computer or laptop first.
In a computer you can use a SATA port, and in laptops, a special 2.5-inch compartment, and, of course, a SATA port. Or, to insert an SSD into a laptop, you need to purchase an external case with a USB connector and then you can easily connect the drive to a laptop or computer.
Using SSD and HDD in a laptop
Usually, in almost any laptop that has an HDD drive, you can change the drive to a SATA-SSD, and in a 2.5-inch form factor. If your laptop has a disk drive, you can replace it with OptibayHD-adapter into which SATA-SSD is connected.
Installing an SSD in a computer
Regular computers do not have space for an SSD drive, since they are smaller in size. Although some computers have bays for these disks. Or you can purchase a special compartment.
Operating system optimization
Once you have installed the SSD, you need to be sure to install the software from the manufacturer. For example, if you install Intel SSD Toolbox software, your device will always have the latest firmware.
Also, you can use it to align partitions and configure the operating system.
If there is no tool for optimizing the SSD and OS, then you can use the AS SSD utility to align partitions.
If in the upper left corner there is a value of 1024 and a green button OK, then this means that everything is fine, but if the red button BAD, then everything is bad. If the Bad button appears, then to fix the problem you can use the Live-USB Parted Magic utility, the program costs about 700 rubles.
What is the best way to organize the data?
When using a 500 GB SSD drive, the best option would be to use one partition for the system (C:), while preferably having some free space. There is also another option: use the entire SSD for the operating system, and a regular hard drive is suitable for storing files.
In any case, if you use the SSD as I wrote just above, it will increase the reserve area that you yourself have allocated, thus the number of memory cells will be increased, and they will replace the failed ones.
Periodically free up disk space
As we know, SSD capacity is very limited, and if you have a 120 GB drive, then naturally you can quickly run out of space. This is worth thinking about, especially since if the disk is used at the limit of its capacity, this greatly harms its characteristics. To solve this problem, you need to clean the disk from files that you no longer need and garbage.
If there are important files that you cannot delete, then move them to another hard drive. To remove files and junk, you can use the CCleaner program. If after cleaning, the fill level is not below 90%, then you should run the disk cleaner.
How to securely delete data from SSD?
It is worth knowing that deleting files from an SSD will be more difficult than from a regular hard drive. To completely remove files from a solid-state drive, you must first remove it using Windows or third-party tools, and then use Eraser to overwrite the free memory several times.
Solid-state drives (SSD drives) are increasingly becoming part of the life of the average personal computer user. Widespread adoption is made possible by the very high speeds at which SSD drives operate. Increasingly, laptop manufacturers are abandoning hard drives in favor of solid-state drives in order to ensure maximum system speed. The choice of an SSD drive has also become relevant, which may seem very difficult to a beginner. Well, let's talk about everything in order.
Looking ahead, I’ll say that it certainly won’t be superfluous. Today, replacing a hard drive is one of the easiest options for upgrading a PC or laptop. Yes, a solid-state drive is more expensive, but immediately after installation, the user will notice a significant increase in speed. It is worth mentioning that you should not expect a serious increase in games. A good SSD will only marginally improve the launch speed of some games. Its main “trump card” is fast loading of the system and opening of folders, files, and so on. Solid state drives perform especially well in laptops. Having installed it, you will notice that the device has become not only faster, but also quieter, lighter, and more autonomous. So, if you want to get a speed boost, be sure to consider an SSD drive.
Volume
A few users immediately decide on the required volume, while others think about this issue for a very long time before buying a high-quality SSD drive. As stated above, such drives do not have a direct impact on performance in games, so it makes sense to buy them for the operating system. See how much your system takes up, as well as the software required. Usually, 60 GB is enough for these purposes, and it is quite difficult to find a smaller volume today. A fast 60 GB SSD costs around 2,000 rubles. If funds allow, then it is better to take a closer look at the 128 GB capacity.
Types
So, we’ll assume that you’re interested in the solid-state drive and you’ve decided on the volume, so let’s move on to a more important question. Many users experience serious problems when choosing a drive type. The Internet is full of advice from experts that even a professional will get confused in. First, let's figure out what distinguishes inexpensive but good SSD drives.
SLC (Single Level Cell)
The technology involves recording 1 bit of information in 1 cell. This type of data is the fastest and most reliable. SLC drives are quite expensive, so they are used only in server computers.
TLC (Triple Level Cell)
The technology involves recording 3 types of memory in one cell. The process is slower and disk resources are consumed faster. TLC discs are distinguished by their low cost and low resources, although they will last quite a long time.
MLC (Multi-Level Cell)
Despite the name, this type of SSD drive writes 2 bits of data per cell. MLC combines a good resource, performance and an affordable price for most users. Today this type is optimal for purchase.
Connection types
Along with the question of how to choose an SSD drive, the question of options for connecting it is relevant. The most common is SATA 3, and this type is also the cheapest. Its bandwidth is 600 Mbps, which is enough for most home computer tasks.
With the proliferation of SSD drives, their speed also increased, which required manufacturers to develop a new type of connection. The solution was the M.2 interface. Its main advantages are speed and compactness. It is worth noting that not every M.2 drive is capable of demonstrating high speed. The reason for this is data transfer interfaces, of which today there are 3 types: SATA, PCI Express 2.0, PCI Express 3.0 (from slowest to fastest). To find out how fast a high-quality SSD drive will work, you should check the specification of the interfaces on the motherboard.
The third connection type is PCI Express, which involves connecting directly to the motherboard. A good SSD drive uses all available speed.
Speed
So, let's move on to a more interesting characteristic of a solid-state drive. Most users first look at the speed of operation. Typically, the drive manufacturer indicates it in large print on the front of the box. It is indicated in megabytes per second and indicates the read and write speed. An inexpensive but reliable SSD drive usually has a read speed of 450 MB/s and a write speed of 350 MB/s. Faster is better.
However, random read and write is much more important. The parameter is responsible for the disk’s ability to work with scattered data around its entire perimeter. The response speed of the system largely depends on it. The manufacturer very often tries not to inform the user about this parameter. If the value is not indicated on the box or store website, then you should refer to the official developer page. In the specifications you need to find the IOPS parameter; its value should be: reading – at least 70,000, writing – at least 50,000. Modern SSD drives often have larger numbers.
Many users may wonder: why do SSD drives with the same type of memory from different manufacturers differ in speed? The fact is that different companies install different controllers in drives - a small chip on which the operation of the disk depends. The total speed of the SSD is directly calculated from it. The better the work done by the company’s programmers, the faster the controller’s operation.
Resources
The resource of a solid-state drive is the number of cell rewrites. Typically, this parameter is specified by the manufacturer, and a special utility helps monitor the health of the disk. Many users are worried that their fast and high-quality SSD drive will very quickly exhaust its supply of overwrites. These experiences are far-fetched. Before your drive cannot be rewritten, it will simply become obsolete, and you will most likely be using a different one. It is also a misconception that the data from the drive disappears. In fact, the user will not only be able to record, but the files will remain on the SSD. Therefore, you don’t have to think too much about the resources of the solid-state drive.
To choose a good SSD drive, you should also pay attention to the access protocols. It would take a long time to describe the moment in full, so I’ll keep it short. The vast majority of modern hard drives and solid state drives use the AHCI protocol. The technology is quite old, it appeared before the era of fast SSD drives, so it does not take into account their specifics. It was replaced by the NVME protocol, which was developed for the needs of solid-state drives. The main advantage was the increase in speed with frequent access to information. They are usually used for server computers or for very serious work. They are characterized by high speed, but are expensive. Before you buy the best SSD drive like this, make sure your motherboard supports the protocol. Sometimes a BIOS update is required for it to work.
Speed increase
Despite a bunch of articles, there are people who still doubt the speed increase. It is quite significant and is observed even with very old hardware. The operating system loads much faster - 2 times, or even faster than a regular HDD. When using a high-quality SSD drive, resource-intensive programs that require a very long wait to run on the hard drive become more responsive. Fans of computer games will also receive, albeit a small, increase in launch speed.
Today, more and more companies are appearing on the market that produce good and inexpensive SSD drives. However, only a few companies have gained particular popularity and distribution.
- Intel. Expensive and high-quality SSD drives from a well-known company are now the standard. Used for servers and serious tasks. A 5-year warranty is provided.
- Crucial. It produces flash memory together with Intel, so the drives are quite similar. A significant difference from its popular colleague is the budget cost, which determines such distribution.
- Samsung. He is engaged in production independently. It produces inexpensive but good SSD drives, thanks to which it is located at the top of the market.
- Corsair. A popular company that produces various components for personal computers. Solid state drives are of decent quality and affordable cost.
- Sandisk. The company is new to the market of high-quality SSD drives, but has already presented several models that have attracted the interest of users.
First SSD, or solid state drives using flash memory, appeared in 1995, and were used exclusively in the military and aerospace fields. The huge cost at that time was compensated by unique characteristics that allowed the operation of such disks in aggressive environments over a wide temperature range.
In the mass market, drives SSD appeared not so long ago, but quickly became popular, as they are a modern alternative to a standard hard drive ( HDD ). Let's figure out what parameters you need to choose a solid-state drive by, and what it actually is.
Device
Out of habit, SSD is called a “disk”, but it can rather be called “ solid parallelepiped", since there are no moving parts in it, and nothing shaped like a disk either. The memory in it is based on the physical properties of the conductivity of semiconductors, so SSD– a semiconductor (or solid-state) device, while a regular hard drive can be called an electro-mechanical device.
Abbreviation SSD just means “ solid-state drive ", that is, literally, " solid state drive" It consists of a controller and memory chips.
Controller– the most important part of the device that connects the memory to the computer. Main characteristics SSD– data exchange speed, power consumption, etc. depend on it. The controller has its own microprocessor that works according to a preinstalled program and can perform the functions of correcting code errors, preventing wear, and cleaning debris.
Memory in drives can be either non-volatile ( NAND), and volatile ( RAM).
NAND memory initially won against HDD only in the speed of access to arbitrary memory blocks, and only since 2012 the read/write speed has also increased many times over. Now in the mass market drives SSD are presented by models with non-volatile NAND-memory.
RAM The memory features ultra-fast read and write speeds, and is built on the principles of computer RAM. Such memory is volatile - if there is no power, the data is lost. Typically used in specific areas, such as speeding up work with databases, it is difficult to find on sale.
Differences between SSD and HDD
SSD differs from HDD First of all, the physical device. Thanks to this, it boasts some advantages, but also has a number of serious disadvantages.
Main advantages:
· Performance. Even from the technical characteristics it is clear that the read/write speed is SSD several times higher, but in practice performance can vary by 50-100 times.
· No moving parts, and therefore no noise. This also means high resistance to mechanical stress.
· Random memory access speed is much higher. As a result, the speed of operation does not depend on the location of files and their fragmentation.
· Much less vulnerable to electromagnetic fields.
· Small dimensions and weight, low power consumption.
Flaws:
· Resource limitation for rewrite cycles. This means that a single cell can be overwritten a certain number of times - on average, this figure varies from 1,000 to 100,000 times.
· The cost of a gigabyte of volume is still quite high, and exceeds the cost of a regular HDD several times. However, this drawback will disappear over time.
· Difficulty or even impossibility of recovering deleted or lost data due to the hardware command used by the drive TRIM, and with high sensitivity to changes in supply voltage: if memory chips are damaged in this way, information from them is lost forever.
In general, SSDs have a number of advantages that standard hard drives do not have - in cases where performance, access speed, size and resistance to mechanical stress play a major role, SDD persistently displaces HDD.
How much SSD capacity will you need?
The first thing you should pay attention to when choosing SSD– its volume. There are models on sale with capacities from 32 to 2000 GB.The decision depends on the use case - you can install only the operating system on the drive, and be limited by the capacity SSD 60-128 GB, which will be quite enough for Windows and installation of basic programs.
The second option is to use SSD as the main media library, but then you will need a disk with a capacity of 500-1000 GB, which will be quite expensive. This only makes sense if you work with a large number of files that need to be accessed really quickly. In relation to the average user, this is not a very rational price/speed ratio.
But there is one more property of solid-state drives - depending on the volume, the write speed can vary greatly. The larger the disk capacity, the faster the recording speed, as a rule. This is due to the fact that SSD capable of using several memory crystals in parallel at once, and the number of crystals grows along with the volume. That is, in the same models SSD with different capacities of 128 and 480 GB, the difference in speed can vary by about 3 times.
Considering this feature, we can say that now the most optimal choice in terms of price/speed can be called 120-240 GB SSD models, they will be enough to install the system and the most important software, and maybe even for several games.
Interface and form factor
2.5" SSD
The most common form factor SSD is a 2.5 inch format. It is a “bar” with dimensions of approximately 100x70x7mm; they may vary slightly among different manufacturers (±1mm). The interface of 2.5” drives is usually SATA3(6 Gbps).Advantages of the 2.5" format:
- Prevalence on the market, any volume available
- Convenient and easy to use, compatible with any motherboard
- Reasonable price
- Relatively low speed among ssds - up to a maximum of 600 MB/s per channel, versus, for example, 1 Gb/s for the PCIe interface
- AHCI controllers that were designed for classic hard drives
mSATA SSD
There is a more compact form factor - mSATA, sizes 30x51x4 mm. It makes sense to use it in laptops and any other compact devices where installing a regular 2.5” drive is impractical. If they have a connector, of course. mSATA. In terms of speed, this is still the same specification SATA3(6 Gbps), and is no different from 2.5".
M.2 SSD
There is another, most compact form factor M.2, gradually replacing mSATA. Designed mainly for laptops. Dimensions - 3.5x22x42(60.80) mm. There are three different lengths of bars - 42, 60 and 80 mm, please pay attention to compatibility when installing in your system. Modern motherboards offer at least one U.2 slot for the M.2 format.M.2 can be either a SATA or PCIe interface. The difference between these interface options is in speed, and quite large at that - SATA drives boast an average speed of 550 MB/s, while PCIe, depending on the generation, can offer 500 MB/s per lane for PCI-E 2.0. and speeds up to 985 Mb/s per PCI-E 3.0 line. Thus, an SSD installed in a PCIe x4 slot (with four lanes) can exchange data at speeds of up to 2 Gb/s in the case of PCI Express 2.0 and up to almost 4 Gb/s when using PCI Express third generation.
The differences in price are significant; an M.2 form factor drive with a PCIe interface will cost on average twice as much as a SATA interface with the same capacity.
The form factor has a U.2 connector, which may have connectors that differ from each other keys– special “cutouts” in them. There are clues B and and also B&M. Differ in bus speed PCIe: key M will provide speed up to PCIe x4, key M speed up to PCIe x2, like a combined key B&M.
B- the connector is incompatible with M- connector, M-connector respectively, with B- connector, and B&M The connector is compatible with any. Be careful when purchasing format M.2, since the motherboard, laptop or tablet must have a suitable connector.
PCI-E SSD
Finally, the last existing form factor is as an expansion board PCI-E. Mounted in the slot accordingly PCI-E, have the highest speed, order 2000 MB/s read and 1000 MB/s write. Such speeds will cost you a lot: it is obvious that you should choose such a drive for professional tasks. 
NVM Express
There are also SSD having a new logical interface NVM Express, designed specifically for SSDs. It differs from the old AHCI in even lower access latencies and high parallelism of memory chips due to a new set of hardware algorithms.There are models on the market with a connector M.2, and in PCIe. The only downside of PCIe here is that it will take up an important slot, which may be useful for another board.
Since the standard NVMe designed specifically for flash memory, it takes into account its features, while AHCI still just a compromise. That's why, NVMe is the future of SSDs, and will only get better and better over time.
What type of SSD memory is better?
Let's understand the types of memory SSD. This is one of the main characteristics SSD, determining the cell rewriting resource and speed.MLC (Multi-Level Cell)- the most popular type of memory. Cells contain 2 bits, as opposed to 1 bit in the old type SLC , which is almost no longer on sale. Thanks to this, there is a larger volume, which means lower cost. Recording resource from 2000 to 5000 rewrite cycles. In this case, “overwriting” means overwriting each cell of the disk. Therefore, for a 240 GB model, for example, you can record at least 480 TB of information. So, such a resource SSD even with constant intensive use, about 5-10 years should be enough (during which time it will still become very outdated). And for home use, it will last for 20 years, so the limited rewrite cycles can be ignored altogether. MLC– this is the best combination of reliability/price.
TLC (Triple-Level Cell)- from the name it follows that here 3 bits of data are stored in one cell at once. Recording density here compared to MLC higher by whole 50% , which means the rewriting resource is less - only 1000 cycles. The access speed is also lower due to the higher density. The cost now is not much different from MLC. It has been widely used in flash drives for a long time. The service life is also sufficient for a home solution, but the susceptibility to uncorrectable errors and “dying out” of memory cells is noticeably higher, and during the entire service life.
3D NAND- This is rather a form of memory organization, and not its new type. There is both MLC, so TLC 3D NAND. Such memory has vertically arranged memory cells, and an individual memory crystal in it has several levels of cells. It turns out that the cell has a third spatial coordinate, hence the prefix "3D" in the memory name - 3D NAND. It is distinguished by a very low number of errors and high endurance due to a larger technical process of 30-40 nM.
The manufacturer's warranty for some models reaches 10 years of use, but the cost is high. The most reliable type of memory available.
Differences between cheap SSDs and expensive ones
Disks of the same capacity, even from the same manufacturer, can vary greatly in price. A cheap SSD may differ from an expensive one in the following ways:· Cheaper type of memory. In ascending order of cost/reliability, roughly: TLC≥ MLC ≥ 3D NAND.
· Cheaper controller. Also affects read/write speed.
· Clipboard. The cheapest SSDs may not have a clipboard at all; this does not make them much cheaper, but it noticeably reduces their performance.
· Protection systems. For example, expensive models have protection against power interruption in the form of backup capacitors, which allow the write operation to be completed correctly and not lose data.
· Brand. Of course, a more popular brand will be more expensive, which does not always mean technical superiority.
Conclusion. What is more profitable to buy?
It is safe to say that modern SSD The drives are quite reliable. The fear of data loss and the negative attitude towards solid-state drives as a class are completely unjustified at the moment. If we talk about more or less popular brands, then even cheap TLC The memory is suitable for budget home use, and its resource will last you for at least several years. Many manufacturers also provide a 3-year warranty.So, if you are limited in funds, then your choice is a capacity of 60-128 GB to install the system and frequently used applications. The type of memory is not so critical for home use - TLC will it be or MLC, the disk will become obsolete before the resource is exhausted. All other things being equal, of course, it is worth choosing MLC.
If you are ready to look into the mid-price segment and value reliability, then it is better to consider SSD MLC 200-500 GB. For older models you will have to pay about 12 thousand rubles. At the same time, the volume is enough for you for almost everything that needs to work quickly on your home PC. You can also take models of even higher reliability with memory crystals 3D NAND .
If your fear of flash memory wearing out reaches panic levels, then it's worth looking at new (and expensive) technologies in the form of storage formats 3D NAND. All jokes aside, this is the future. SSD– high speed and high reliability are combined here. Such a drive is suitable even for important server databases, since the recording resource here reaches petabyte, and the number of errors is minimal.
I would like to include drives with an interface into a separate group PCI-E. It has high read and write speed ( 1000-2000 Mb/s), and on average more expensive than other categories. If you prioritize performance, then this is the best choice. The disadvantage is that it takes up a universal PCIe slot; motherboards of compact formats may only have one PCIe slot.
Beyond competition - SSD with NVMe logical interface, the reading speed of which exceeds 2000 MB/s. Compared to compromise logic for SSD AHCI, has much greater queue depth and concurrency. High price in the market, and the best characteristics - the choice of enthusiasts or professionals.