What is affected by hard drive capacity? Buffer memory: main characteristics

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RAM ensures the normal functioning of a personal computer, as well as the rapid execution of programs and tasks. Its volume determines how many tasks a user can simultaneously perform on his computer. There are some elements in the computer that are also equipped with memory. Let's look at what buffer (or cache) memory is, what its tasks are, its advantages, and how to calculate the required volume.

Cache memory is an area for temporary storage of data. Information that has been read from the hard drive but has not yet been transferred for further processing is stored here. The need for such storage arose as a result of the discovery of a large difference between the period of time over which data is read and the throughput of the system.

Other PC elements also have some kind of buffer. For example, a printer that can move on to the next task, but still print the material that was previously specified. Video cards, network cards, etc. also have buffer memory.

The main technical properties of a cache are its capacity and performance. Modern devices differ significantly from each other in terms of such timing characteristics, as well as buffer volume. The larger the cache memory, the more information it holds. This means that the computer can produce results without accessing the hard drive often.

Thus, the system performance itself increases, and indirectly extends the life of the hard drive. The latter depends directly on the user and how and for what he uses the hard drive. For example, a hard drive will last longer if you watch movies in a browser, rather than downloading via torrent and opening with a video player.

Cache volumes

When choosing a personal computer, it is important to pay attention to such an indicator as the amount of buffer memory. Since it periodically needs to be rebooted and cleared, the larger the cache, the better. Modern PAs are equipped with 8, 16, 32 and 64 MB, but the buffers have a capacity of 128 and 256 MB.

Although modern laptops and computers are most often equipped with a large cache memory, smaller ones are already a rarity. When choosing a device, users rarely pay attention to this indicator, since it does not directly depend on the price. And also the parameter is not key when choosing a computer. Here you need to pay attention to other indicators, since usually the system’s own memory is quite enough to perform operations.

Cache types

Buffer memory that is located in one fixed location is called a direct-mapped cache. If it is located anywhere, then it is called fully associative memory. In this case, the buffer volume is completely used, the data can be deleted after it is completely filled, but searching for information is quite difficult.

A compromise option could be a multiple or partially associative cache. In this case, the buffer lines are combined into groups. In this case, a block that corresponds to a specific group can be placed in any line, and the corresponding value is placed in the tag. There is a kind of associativity principle at work here, but a certain block only falls into one group or another. This is somewhat similar to a direct mapping buffer.

The multiple associative type of buffer memory on disk is the most common, as it has high speed and good memory utilization. But at the same time, the direct mapping cache, which is cheap and simple, is only slightly inferior in its characteristics.

the main task

Buffer memory is designed for temporary storage and reading of information. But this indicator is not the main one when determining the efficiency of a hard drive. Also important is the algorithm for exchanging data with the buffer, as well as how well the work is done to prevent errors.

Buffer storage contains information that is used most often. At the same time, performance increases several times, since it is loaded directly from the cache. There is no direct access to the hard drive and its sectors, since there is no need for physical reading. This process is quite long, although it is measured in milliseconds, but data from the buffer can be obtained many times faster.

Advantages

Although the main advantage of buffer memory is fast data processing, there are other advantages. A hard drive with a large buffer can relieve the processor or use it minimally. This way, the computer will not be overloaded and will last longer.

The cache is also a kind of accelerator, ensuring efficient and fast operation of the entire system. This reduces software startup time when data already contained in the cache is required.

For the average user, 32 or 64 MB is enough for work. A larger size loses its significance, since when interacting with large files, this difference is negligible. In addition, it is unlikely that anyone will want to overpay for a larger buffer.

How to find out the amount of buffer memory on your hard drive?

Not every user is interested in such a characteristic as cache size (as opposed to hard drive size). The information is usually contained on the packaging of the device. You can also find data online or use HD Tune, which is free.

It is designed to securely delete data, assess the state of the device, and scan and fix errors in the system. Additionally, you can use it to obtain information about the hard drive.

To find out the amount of buffer memory in MB, you need to download the HD Tune utility and run it. Next, in the “Information” tab, you need to find a line called “buffer”, which will show how large the cache is installed in this device.

Experts note that for the average PC user, a size of 128 MB is suitable. If the computer is used primarily for games, you should focus on a larger cache size.

If you want to know what hard drive cache is and how it works, this article is for you. You will learn what it is, what functions it performs and how it affects the operation of the device, as well as the advantages and disadvantages of the cache.

Understanding Hard Drive Cache

The hard drive itself is a rather leisurely device. Compared to RAM, a hard drive is several orders of magnitude slower. This also causes a drop in computer performance when there is a lack of RAM, since the shortage is compensated by the hard drive.

So, hard drive cache is a kind of RAM. It is built into the hard drive and serves as a buffer for reading information and its subsequent transfer to the system, and also contains the most frequently used data.

Let's look at why hard drive cache is needed.

As noted above, reading information from a hard drive occurs very slowly, since moving the head and finding the required sector takes a lot of time.

It is necessary to clarify that by “slowly” we mean milliseconds. And for modern technologies, a millisecond is a very long time.

Therefore, just like the hard drive cache, it stores data physically read from the disk surface, and also reads and stores sectors that are likely to be requested later.

This reduces the number of physical accesses to the drive while increasing performance. The hard drive can work even if the host bus is not free. The transfer speed can increase hundreds of times for similar requests.

How does hard drive cache work?

Let's look at this in more detail. You already have a rough idea of what the hard drive cache is intended for. Now let's find out how it works.

Let's imagine that the hard drive receives a request to read 512 KB of information from one block. The necessary information is taken from the disk and transferred to the cache, but along with the requested data, several neighboring blocks are also read. This is called prefetching. When a new request for a disk arrives, the drive microcontroller first checks for the presence of this information in the cache and if it finds it, it instantly transmits it to the system without accessing the physical surface.

Since cache memory is limited, the oldest blocks of information are replaced with new ones. This is a circular cache or circular buffer.

Methods for increasing hard drive speed using buffer memory

Adaptive segmentation. The cache memory consists of segments with equal amounts of memory. Since the sizes of the requested information cannot always be the same size, many cache segments will be irrationally used. Therefore, manufacturers began to make cache memory with the ability to change the size of segments and their number.
Prefetch. The hard drive processor analyzes the previously requested and currently requested data. Based on the analysis, it transfers information from the physical surface that is more likely to be requested at the next point in time.
User control. More advanced models of hard drives allow the user to control the operations performed in the cache. For example: disabling the cache, setting the size of the segments, toggling the adaptive segmentation feature, or disabling prefetching.

Which gives the device more cache memory

Now we’ll find out what capacities are equipped and what the cache memory in the hard drive provides.

Most often you can find hard drives with a cache size of 32 and 64 MB. But there were also 8 and 16 MB left. Recently, they began to produce only 32 and 64 MB. A significant breakthrough in performance occurred when 16 MB began to be used instead of 8 MB. And between caches of 16 and 32 MB, there is no longer any significant difference, as well as between 32 and 64.

The average computer user will not notice a difference in the performance of hard drives with a 32 and 64 MB cache. But it is worth noting that the cache memory periodically experiences significant loads, so it is better to purchase a hard drive with a higher cache capacity if you have the financial opportunity.

Main advantages of cache memory

Cache memory has many advantages. We will consider only the main ones:

Disadvantages of cache memory

The speed of the hard drive does not increase if the data is written randomly on the disks. This makes it impossible to prefetch information. This problem can be partially avoided if you defragment it periodically.
The buffer is useless when reading files larger than can fit in the cache memory. So, when accessing a file of 100 MB in size, a 64 MB cache will be useless.

Additional Information

You now know the hard drive and what it affects. What else do you need to know? Currently, there is a new type of drive - SSD (solid state). Instead of disk platters, they use synchronous memory, like flash drives. Such drives are tens of times faster than conventional hard drives, so having a cache is useless. But such drives also have their drawbacks. Firstly, the price of such devices increases in proportion to the volume. Secondly, they have a limited cycle time for rewriting memory cells.

There are also hybrid drives: a solid-state drive with a regular hard drive. The advantage is the ratio of high operating speed and large volume of stored information with a relatively low cost.

Today, a common storage device is a magnetic hard drive. It has a certain amount of memory designed to store basic data. It also has a buffer memory, the purpose of which is to store intermediate data. Professionals call the hard disk buffer the term “cache memory” or simply “cache”. Let's figure out why the HDD buffer is needed, what it affects and what size it is.

The hard disk buffer helps the operating system temporarily store data that was read from the main memory of the hard drive, but was not transferred for processing. The need for transit storage is due to the fact that the speed of reading information from the HDD drive and the OS throughput vary significantly. Therefore, the computer needs to temporarily store data in a “cache” and only then use it for its intended purpose.

The hard disk buffer itself is not separate sectors, as incompetent computer users believe. It is a special memory chip located on the internal HDD board. Such chips can operate much faster than the drive itself. As a result, they cause an increase (by several percent) in computer performance observed during operation.

It is worth noting that the size of “cache memory” depends on the specific disk model. Previously, it was about 8 megabytes, and this figure was considered satisfactory. However, with the development of technology, manufacturers were able to produce chips with larger amounts of memory. Therefore, most modern hard drives have a buffer whose size varies from 32 to 128 megabytes. Of course, the largest “cache” is installed in expensive models.

What impact does a hard drive buffer have on performance?

Now we’ll tell you why the size of the hard drive buffer affects computer performance. Theoretically, the more information is in the “cache memory”, the less often the operating system will access the hard drive. This is especially true for a work scenario where a potential user is processing a large number of small files. They simply move to the hard drive buffer and wait there for their turn.

However, if the PC is used to process large files, then the “cache” loses its relevance. After all, information cannot fit on microcircuits, the volume of which is small. As a result, the user will not notice an increase in computer performance, since the buffer will be practically not used. This happens in cases where the operating system will run programs for editing video files, etc.

Thus, when purchasing a new hard drive, it is recommended to pay attention to the size of the “cache” only in cases where you plan to constantly process small files. Then you will really notice an increase in the performance of your personal computer. But if the PC is used for ordinary everyday tasks or processing large files, then you don’t need to attach any importance to the clipboard.

The question of upgrading a computer sooner or later arises before every user. Perhaps you are building a new PC or want to store more information on your machine and use it efficiently. To do this, you cannot do without purchasing a new high-quality HDD (hard disc drive). In each case, you need to have a clear understanding of how to choose a good hard drive that will satisfy all your needs and be reliable in operation.

In each case, you need to have a clear understanding of how to choose a good hard drive that will satisfy all your needs and be reliable in operation.

The first step is to decide for what purpose you plan to use the data drive. Depending on the scope of application, there are different price categories for hdd. Manufacturers produce series of products designed primarily for: Archive function (data storage); Daily work (regular writing and reading of information);

Active work with a large amount of data, where increased reliability is needed - such solutions are suitable for the corporate sector.

Physical dimensions of hdd

Two form factors have been developed that determine the physical dimensions of hard drives. More compact drives are used in portable PC models, while larger ones are designed for desktop computers. The following options are distinguished: 2.5’’ (inches) – for laptops of any configuration, in order to connect such a drive to a stationary machine, special mounts for the case will be required;

3.5’’ (inches) – for personal workstations, considered the “gold standard” for desktop computers.

Hard drive interface

Before purchasing, be sure to find out through which interface the new drive will be connected to the motherboard. A mismatch between the interfaces on the board and the hdd leads to the complete impossibility of using it or can significantly reduce the speed of operation.

Older models used the IDE (or Parallel ATA) interface, which involves parallel connection of the device to the computer. In recent years, it has been replaced by the more modern and faster SATA (Serial ATA) interface, which serves to daisy chain hard drives to the motherboard and offers better read and write speeds than its predecessor.

There are three generations of SATA interfaces: SATA I, which transmits data at a speed of 1.5 Gbit per second, is also becoming a thing of the past; SATA II, which transmits data at speeds of up to 3 Gbit per second;

SATA III, the fastest interface with a transfer speed of about 6 Gbit per second;

Note that desktop and mobile machines using an IDE connector are not compatible with each other, therefore, if there is a need to connect a hard drive from a laptop to a PC or vice versa, you will need a special adapter.

SATA II and SATA III connectors are designed in such a way that they completely solve this problem. They are fully compatible, but keep in mind that if you connect a SATA III hard drive to a SATA II motherboard, it will run slower and perform at the same level as the second generation interfaces.

If you are thinking about how to choose a hard drive for your computer, then it is advisable that the model you choose has a second or third generation interface (SATA II, SATA III).

Capacity or volume of hdd

When choosing the storage capacity, proceed from your needs and the tasks that will be performed by the computer where you plan to connect the device.

If you are choosing a new hard drive for a desktop computer, then you should focus on the following numbers: Volume 320 GB, if the machine is needed to use text editors and view web pages; Volume from 500 GB to 1 TB, if, in addition to the most common programs, multimedia files (music, photos, films) will be stored on the disk and it is planned to install modern games;

A capacity of 2 to 4 TB will be needed for a PC on which professional processing of graphic files and video clips will be carried out, as well as storage and processing of large amounts of information.

Installing a hdd with a capacity of more than 2 GB is not possible on machines that do not support the UEFI standard, which is gradually replacing motherboards with BIOS. Therefore, if you have chosen a very large capacity hard drive, make sure that your computer belongs to the right class of PC. The BIOS will not be able to identify and work correctly in the future with such a device.

When buying a new hard drive for a laptop, be guided by the following data: From 320 to 500 GB, if you have a netbook, which is used as an additional machine when traveling outside the home;

From 750 GB to 1 TB, if you use a laptop as a basic workstation and, in addition to the installed operating system, you need to store a large amount of information and work with complex software.

If you need to choose a hdd, keep in mind that you need to have additional space on it for backup copies of files. This will increase the reliability of the disk and reduce the likelihood of sudden loss of valuable data. In some cases, the optimal solution will be if you select several drives for a special information duplication system.

Optimal hard drive speed

The basic principle of operation of a hard drive is the rotation of the disk plates around their axis, during which the magnetic head reads and writes data. The number of revolutions depends on the spindle speed. In proportion to the increase in this parameter, the intensity of information exchange with the system and the speed of the disk increase.

There are several types of disks based on the values of this indicator: Models operating at a speed of 5400 rpm - used mainly in laptops (for desktop PCs you can choose for archival purposes), have low power consumption, are not noisy, but work quite slowly; Drives with operating speeds of 7200 rpm - the most popular hard drives have such characteristics, since they are optimal for solving most problems that users face;

Devices with operating speeds from 10,000 to 15,000 rpm are very fast and productive, used in the corporate sector, designed for powerful servers (they are rarely chosen for home use in case of non-standard needs);

Buffer memory (cache) size for hdd

Anyone who is collecting information on how to choose a hard drive for a PC should pay attention to the cache size of this device. It stores data that has been extracted from the media but has not yet been loaded into RAM, and data that came from other system components and has not yet been written to the hdd. Too small a buffer memory size can slow down the disk.

On the modern market there are devices whose cache volume ranges from 16 to 64 MB. A good hard drive should have a buffer capacity of 32 MB or 64 MB, which will be the key to its effective service. It is usually recommended to choose a hard drive with a large cache size.

Options for reading and writing information

The main parameters that determine how efficiently the device will exchange data with the rest of the computer are the speeds of linear data reading and writing, as well as random access time.

The speed of the device is directly determined by the linear reading speed, which should be remembered by every potential buyer who is thinking about which hard drive to choose for the system. The optimal value for this characteristic is considered to be in the range from 120 to 140 Mb/s. You should not purchase a model with a linear read speed below 100 MB per second.

The second important indicator of device performance is random access time. It especially affects the time with which the head reads small files from the disk. For a high-quality hard drive, this figure is no more than 14 ms. Operational problems arise with devices whose random access time reaches 16-19 ms.

Be careful, because these indicators are not indicated by the manufacturer on the device packaging and cannot be found on online store websites. They are determined using special software (for example, HD Tune 2.5) only on a working drive. Therefore, one of the instructions on how to choose a good hard drive is to search and study in detail reviews and tests of the hdd model you like. It is from them that you can find out the real numbers and independently correctly evaluate, before purchasing, how this or that hard drive behaves in practice.

The best hard drive manufacturers

There are several leaders on the hdd manufacturer market that guarantee the high quality of their products, their reliability and durability. Before purchasing a hard drive, be sure to check the reputation of its manufacturer, as purchasing a model from an unknown company may cause data loss on your PC in the future.

Important information for those who want to know how to choose the right hard drive for a computer is that high-quality models are offered primarily by Seagate and Western Digital (WD). You can also find devices from Hitachi and Samsung in specialized stores, but their percentage of the total number of devices offered is not too large.

Manufacturers launch various series of models on the market that are aimed at private and corporate clients, which causes differences in price, volume and technical characteristics of products.

For example, Western Digital uses simple color coding for its products, which can be used to correctly understand the specifics of using a particular device.

Hard drives with a blue mark on the case (Cover Blue) are budget solutions that have good performance parameters, but they should not be used to store particularly important information.

Cover Green drives are models that require little power to operate, have average performance, and produce little noise.

Devices with a red casing marking (Cover Red) are drives with high speed and high performance, equipped with the most modern control controllers.

HDDs with a black designation on the case (Cover Black) contain the best features of models with a red marking and guarantee very high reliability of data storage.

Thanks to this detailed instruction, purchasing a good hard drive for your PC will not cause you any difficulties, because we talk about computers in Russian and make the information accessible to every user. Following this algorithm will allow you to choose exactly the hdd that will become a reliable component of your machine and will help in solving all current problems.

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Form factor, buffer size and other HDD characteristics

In previous articles that dealt with the characteristics of HDDs, parameters such as spindle rotation speed and the level of noise emitted by the hard drive were discussed in some detail.

The HDD interface was also discussed, where the main features and differences between the SATA interface and the outdated IDE were discussed. And of course, we didn’t forget, perhaps, the most important characteristic - the capacity of the hard drive.

In this material we will talk about the remaining characteristics of hard drives, which are no less important than the above.

Hard drive form factor

At the moment, two form factors of hard drives are widely used - 2.5 and 3.5 inches. The form factor largely determines the dimensions of hard drives. By the way, a 3.5” hard drive can accommodate up to 5 drive platters, and a 2.5” hard drive can accommodate up to 3 platters. But in modern realities, this is not an advantage, since the developers have determined for themselves that installing more than 2 platters in ordinary high-performance hard drives is not advisable. Although, the 3.5” form factor does not intend to give up at all and, in terms of demand, confidently outweighs 2.5” in the desktop segment.

That is, for a desktop system, for now it makes sense to purchase only 3.5”, since among the advantages of this form factor, one can note a lower cost per gigabyte of space, with a larger volume. This is achieved due to a larger platter, which, with the same recording density, can accommodate a larger volume of data than 2.5”. Traditionally, 2.5” has always been positioned as a form factor for laptops, largely due to its dimensions.

There are other form factors. For example, many portable devices use 1.8” form factor hard drives, but we will not dwell on them in detail.

Hard drive cache size

Cache memory is a specialized RAM that acts as an intermediate link (buffer) for storing data that has already been read from the hard drive, but has not yet been transferred directly for processing. The very presence of the buffer was caused by a significant difference in operating speed between the rest of the system components and the hard drive.

As such, a characteristic of HDD cache memory is volume. At the moment, the most popular hard drives are those with 32 and 64 MB buffers. In fact, buying a hard drive with a large amount of cache memory will not double the performance as it might seem based on classical arithmetic. Moreover, testing has shown that the advantage of hard drives with a 64 MB cache manifests itself quite rarely and only when performing specific tasks. Therefore, if possible, it is worth purchasing a hard drive with a larger cache memory, but if this comes at a significant cost to the price tag, then this is not the parameter that you should focus on first.

Random access time

The hard drive random access time indicator characterizes the time during which the hard drive is guaranteed to perform a read operation anywhere on the hard drive. That is, in what period of time will the reading head be able to reach the most distant sector of the hard drive. This largely depends on the previously discussed characteristics of the spindle speed of the hard drive. After all, the higher the rotation speed, the faster the head can reach the desired track. In modern hard drives this figure ranges from 2 to 16 ms.

Other HDD characteristics

Now let’s briefly and briefly list the remaining characteristics of hard drives:

Energy consumption – hard drives consume very little. Moreover, the maximum power consumption is often indicated, which occurs only at intermediate stages of operation during peak load. On average it is 1.5-4.5 W;
Reliability (MTBF) – the so-called time between failures;
Data transfer speed – from the external zone of the disk: from 60 to 114 Mb/s, and from the internal zone – from 44.2 to 75 Mb/s;
Number of input/output operations per second (IOPS) – for modern hard drives this figure is about 50/100 op/s, with random and sequential access.

So we looked at all the characteristics of hard drives using a small series of articles. Naturally, many parameters intersect and, to some extent, influence each other. But, on the basis of information regarding all these parameters, you can model a future device for yourself, and when choosing, clearly understand which model should be given preference in your particular case.

But such toys can be made from old hard drives, or rather from the components of a hard drive. For example, the wheels are made from a spindle motor of a hard drive, which drives an axle with a readout head.

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How to choose a hard drive

Hard disk (HDD) is an important element of the system unit. It stores user data and files. To choose the right hard drive, you need to know only a few parameters.

Basic characteristics of the hard drive

Hard disk capacity

When choosing a hard drive, the first parameter you should pay attention to is capacity. Volume – the amount of space on the hard drive, that is, this parameter displays how much information (movies, documents, folders, etc.) you can write to the hard drive. The volume of modern media is measured in gigabytes or terabytes. The larger the hard drive capacity, the better. It is better to buy a hard drive with one or more terabytes.

Interface

The hard drive is connected to the motherboard via an interface cable. Internal hard drives, connected to the computer via an interface (IDE or SATA). IDE is an outdated interface. Modern hard drives are connected to the computer via the SATA interface. There are several options for the SATA interface: SATA I (up to 1.5 Gbit/s), SATA II (up to 3 Gbit/s), SATA III (up to 6 Gbit/s). The higher the data transfer rate through the interface, the better. The optimal hard drive interface option is SATA III.

Spindle speed

The speed of data exchange depends on the spindle rotation speed. It is measured in revolutions per minute (rpm). The higher the spindle speed, the better. The optimal option is 7200 rpm.

Buffer memory (Cache memory)

Buffer memory is hard disk memory that stores data that has already been read from the hard disk, but has not yet been transmitted through the interface. The larger the buffer memory, the more likely it is that the necessary data is located in it and does not need to be looked for on disk. Investigator, increase the speed of the hard drive. At the moment, the maximum memory capacity is 64 MB.

Form factor

The form factor of a hard drive is its physical dimensions (width, height, thickness). There are two main form factors: 2.5 inches (2.5”) and 3.5 inches (3.5”). Hard drives with a 2.5" form factor are designed for use in laptops, although they can be inserted into a regular system unit using additional mounts and adapters. Due to the specific nature of laptop operation, budget 2.5" hard drives, in most cases, have a spindle rotation speed of 5400 rpm.

3.5” hard drives are designed for installation in a regular system unit. When assembling a home computer, it is better to buy a 3.5" hard drive.

Using these tips, you can choose a good hard drive for your computer.

A hard drive (hard drive, Hard Disk Drive, HDD) is a device designed to store all information on a computer. All movies, music, photos, documents, all system files are stored on it. Therefore, I have a special relationship with this device; I always carefully monitor its condition and constantly make backup copies of important information so as not to lose it. I will definitely tell you how to make backup copies in one of my notes.

If your computer suddenly does not turn on, do not be alarmed, most likely all the information remains intact. If desired and with certain skills, all information from one hard drive can be copied to another. You can read more about this in my article on how to copy data from a hard drive or how to “clone a disk.”

So, let's start looking at the characteristics of the hard drive.

Here are the main ones:

hard drive type;
storage volume;
disk form factor;
interface;
buffer memory volume;

I have listed as many as 5 characteristics, but we will deal with them quickly, since there is nothing complicated about them, and some will already be familiar to you from previous lessons.

Drive type

There are two types of drives:

1) HDD– Hard disk drive is the most common type of drive, which consists of metal alloy plates coated with a layer of ferromagnetic material. All information is recorded on these plates, which rotate at a very high speed - 5400/7200 rpm. In this case, information is read by the reading head without touching the surface of the plates, thereby not damaging it and increasing the service life of the device.

These devices are used in the vast majority of computers because their cost is low.

2) SSD– Solid state drive – a storage device based on memory chips. SSD drives appeared relatively recently and quickly took their place in the market. Currently, solid-state drives are used in compact devices: laptops, netbooks, communicators and smartphones.

I will give the disadvantages and advantages of SSD drives.

Flaws:

limited number of rewrite cycles. Depending on the type of memory cells used, from 10,000 to 100,000 times;
the problem of compatibility of SSD drives with some versions of operating systems of the Windows family, which do not take into account the specifics of SSD drives, thereby reducing their service life;
the price of a gigabyte of SSD drives is significantly higher than the price of a gigabyte of HDD;
impossibility of recovering deleted information using recovery utilities;

Advantages:

absence of moving parts, and, as a result, high mechanical resistance;
high read/write speed;
low power consumption;
complete absence of noise due to the absence of moving parts and cooling fans;
stability of file reading time, regardless of their location or fragmentation;
small dimensions and weight;
Great potential for the development of storage devices and production technologies.

Despite the many advantages of SSD drives, I personally still use traditional HDDs. Their productivity is enough for me to carry out any tasks, and time-tested technologies are reliable enough to trust them with important information. Well, of course, my choice is influenced by the cost of drives.

Storage capacity

Obviously, the larger the hard drive, the more important information we can place on it. The capacity of hard drives is measured in billions of bytes (GB - gigabytes) or trillions of bytes (TB - terabytes). The capacity of modern drives reaches up to 4TB in one device, but we must remember that if desired, we can install several such hard drives in the system.

Of course, the higher the storage capacity, the more expensive its cost, and the cost of SSDs is directly proportional to their capacity, while the cost of traditional hard drives depends on the number of platters and grows more slowly as the storage capacity increases.

Form factor

The form factor determines the size of the drive. There are 3 sizes of modern hard drives: 1.8”, 2.5”, 3.5”.

HDD hard drives can have sizes of 2.5 and 3.5 inches. 3.5-inch drives are installed inside the system unit, and 2.5-inch drives are used in laptops and external hard drives.

SSD drives can have a form factor of 2.5 inches or 1.8 inches. As I wrote earlier, they are used in laptops, netbooks, communicators and smartphones.

Interface

For order, we list all the popular interfaces:

SATA, SATA2, SATA3;

Now a few words about each of the connectors.

IDE is an old connector that can be easily distinguished from others by its wide cable from the hard drive to the motherboard. Modern computers do not use such a connector, but I can’t help but mention it, since it is still found in older computers. The IDE connector is becoming less and less common on motherboards.

The IDE was replaced by the SATA connector, which also became outdated and was in turn replaced by SATA2 and now the SATA3 connector is increasingly used. I combined all the connectors into one item, since they are all identical in shape and differ only in the data transfer speed - 1.5 Gb/s, 3 Gb/s, 6 Gb/s, respectively. But it should be remembered that in order for a hard drive with a connector, for example, SATA3, to work at maximum efficiency, the motherboard must also have a SATA3 connector installed. If a SATA2 connector is installed on the motherboard, then a hard drive with a SATA3 interface will still work, but information will be transferred at a speed of 3 Gb/s.

Although, the situation with a transfer speed of 6 Gb/s is more like a marketing ploy. The fact is that the vast majority of modern drives still cannot completely fill a 3 GB/s channel, since the speed of reading and writing to the disk is significantly lower than this speed.

And the last interface is micro-SATA. This connector appeared quite recently; 1.8” SSD drives are connected through it. Micro-SATA connectors have already begun to appear on modern motherboards, but even if the motherboard you have chosen does not have such an interface, the drive can be connected via a micro-SATA to SATA adapter.

Buffer memory capacity (CACH)

Let's figure out what it is. A buffer is an intermediate memory designed to smooth out differences in read/write and transfer speeds across the interface. In modern disks it usually varies from 8 to 128 MB.

For you, my readers, I will clarify that the buffer volume does not provide a significant increase in system performance, so you should not pay attention to it as a key element. Any noticeable difference in time can be obtained by copying very large amounts of information.

By tradition, we will consider the railway markings from the supplier’s catalog.

The article turned out to be quite long, but I hope that someone will appreciate it, and my efforts will not be in vain.

Well, that's all for today. So, slowly, we learned another lesson that should help in achieving our common success. I hope this material will help you make the right choice.