How to partition a hard drive. How to divide a hard drive into partitions Work with disks using special utility programs

Below is a table for calculating rectangular plates of constant stiffness with Poisson's ratio μ = 0.3. The plates are rigidly clamped on two sides and hinged on the other two sides, while the rigidly clamped and hinged sides converge at two diagonally opposite vertices of the rectangle. The plates are subjected to a uniformly distributed load q:

Table 394

And a few more explanations for this table:

1. The values ​​of the coefficients were checked according to various engineering reference books, in particular, according to the book "Calculation of plates" by D.V. and E.D. Weinbergov.

2. h- plate height. Often, letters are used to indicate the length and width of the plate. A And b, however, I decided to designate the length of the plate - l, and the width of the plate - b. And although this looks somewhat paradoxical, since the length of the plate is less than or, in the boundary case, equal to the width, nevertheless, this allows (rather conventionally) to consider the plate as a beam.

3. M x X. At the point ABOUT z. Respectively Mz- diagram of moments acting on sections perpendicular to the axis z. At the point ABOUT currently trying to rotate the cross section around the axis x. The greater the ratio l/b, the more the type of diagram changes Mz. Minus in the value of moments in points H 1 And TO(on the rigid supports of the plate) means that at these points the tension will be in the upper zone of the plate.

4. The table does not contain the values ​​of some coefficients for plates with an aspect ratio of more than 2, for the reason that such plates are easier to consider as just a beam with rigid clamping on one support and hinged support on the other, however, if you want to make more accurate calculations for the plates with a large aspect ratio, you can take the value of the coefficient lower in this column.

5. When the value of Poisson's ratio decreases, the value of some coefficients will increase. For example, when μ = 1/6 the value of the coefficients k 2 and k 3 (with the aspect ratio l/b = 1) will be 11% greater than that given in the table, and the value of the coefficients k 4 and k 5 will be the same. The reason for this is the change in the geometry of the cross section (and, accordingly, the change in the moment of inertia of the cross section) with a change in the Poisson's ratio. Theoretically, it would be possible to give another table that allows you to determine the values ​​​​of the coefficients at a lower value of the Poisson's ratio, but I decided not to do this. For people who are engaged in the calculation of a single structure only once in their life, simplicity and safety margin are much more important than the nuances of rather complex plate calculations. Well, for everyone else, there are endless expanses of the Internet and libraries.

6. For intermediate values ​​of the ratio l/b coefficient values ​​are determined by interpolation.

2.5" and 3.5" Hard Drive Solutions

Hard drives in two form factors 2.5" and 3.5" - practical differences and applications.

Often, instead of specifying a specific hard drive form factor in inches(and the double quote denotes exactly inch), computer hardware vendors use the abbreviations SFF and LFF, abbreviations for Small Form Factor and Large Form Factor, respectively. It is easy to guess that any (both SATA and SAS) hard drives of a smaller form factor 2.5" received the designation SFF HDD and more 3.5" - LFF HDD. It's no secret that in modern high-performance hard drives of 3.5" and 2.5" form factors, manufacturers use platters of the same size - from 2.5" HDD. Therefore, often, both the capacity and performance parameters of 2.5" and 3.5" hard drive models from the same manufacturer look the same Moreover, some manufacturers have announced that they are no longer producing high-performance 3.5" HDDs, leaving top models of HDDs in 2.5" form factor only. Availability of high-performance 3.5" HDDs is steadily declining. Based on the realities of the modern market, manufacturers consider it economically inexpedient to use more than 2 platters inside one hard drive. For reference, it is possible to install up to 3 platters in a 2.5" hard drive (15mm high), and up to 5 platters in a 3.5" HDD.

2.5" drive

3.5" drive

What about those consumers who cannot or do not want (for various reasons) to use modern hard drives of the 2.5" form factor? Manufacturers offer an intermediate solution - the use of 2.5" hard drives in a 3.5" form factor. As a 3.5" hard drive, a regular 2.5" hard drive is offered, installed at the factory by the manufacturer in a special metal mounting case - a carriage. It should be noted that the removal of this hard drive from the mounting case by some manufacturers is not compatible with the warranty. Of the undoubted advantages of this design, it should be noted that the engineers of manufacturing companies accurately calculate the dimensions and rigidity of the structure, the location of connectors and mounting holes is standard for 3.5" hard drives, and optimal cooling of the hard drive installed inside is ensured.

If a move to a smaller form factor is inevitable, what will consumers get from moving to a 2.5" hard drive form factor?
What are the differences, pros and cons of disk subsystems based on hard disks of various form factors and their scope? In two words, what's the difference?

Obviously, the smaller the size of the hard disk, the more such hard disks must fit inside the server.

Today, the following number of hard drives are traditionally installed in rack-mount servers:

In general (as can be seen from the table), it is possible to install 2 times more 2.5" hard drives in servers compared to servers of the same size, but with 3.5" hard drives.

As mentioned earlier, in the segment of enterprise-class hard drives, the maximum capacity of drives of two different form factors is the same, based on this, the use of a disk subsystem with 2.5" bays allows you to double the maximum total storage capacity. And even when using low-priced hard drives range, in which, today, the maximum capacity of 3.5" form factor hard drives is about 2 times larger than that of 2.5" drives, the maximum capacity of disk subsystems with bays of different form factors will be approximately the same.

As an additional bonus of using 2.5" hard drives, it is obvious that due to smaller dimensions (a 2.5" drive is less than a 3.5" drive in depth), the disk subsystem in the server occupies a smaller volume, which allows manufacturers to slightly reduce the size of servers. It should also be noted that most modern SSDs (solid state drives) are available in the 2.5" form factor and the use of 2.5" bays in the server guarantees compatibility when installing SSD drives, and, most importantly, in the future - with a possible server upgrade.

For comparison, two 2.5" hard drives with 10.000rpm (revolutions per minute) enterprise class on a good RAID controller will outperform one 3.5" drive with 15.000rpm in performance. At the same time, the price of two 2.5" 10.000rpm drives with a capacity of 300GB each and one 3.5" 15.000rpm drive with a capacity of 600GB will be approximately the same.

Such a parameter as the linear read / write speed on external tracks, theoretically, should be higher for 3.5" hard drives than for 2.5" hard drives (at the same spindle speed and at the same recording density) simply due to the physically larger size of the platters, but in reality there are differences insignificant, since high-performance hard drives of different form factors often contain platters of the same size.

In general, the more hard drives in the server, the greater the power consumption (more powerful power supplies should be), and the greater the heat dissipation (the server's ventilation system and cooling costs should be more powerful). However, compared to 3.5" hard drive models, modern 2.5" hard drives have 2 times less power consumption (in all modes) and, as a result, less heat dissipation and cooling costs. Thus, a server with 24 2.5" hard drives consumes electricity and heats the environment less than a server with 12 3.5" hard drives.

The reliability of hard drives is always given great attention. Due to the reduction in size (and additional engineering solutions) 2.5" hard drives have increased resistance to vibration and mechanical stress. This is confirmed by the manufacturers themselves, the time between failures (MTBF) for the latest models of 2.5" hard drives is 2 million hours, compared to the best models of 3.5" hard drives, whose MTBF is declared at the level of 1.3-1.6 million hours.

And lastly, despite the fact that this is not relevant in servers, 2.5" drives produce slightly less noise during operation compared to 3.5" models.

As a result, we can briefly formulate the pros and cons, as well as the scope of hard drives of various form factors.

Advantages of hard drives in different form factors

3.5" LFF - more volume of one disk, less price per gigabyte:
• at the same recording density, more information is placed on a larger platter
• the maximum capacity of one HDD is larger (in the low price range hard disk segment)
• cheaper cost per gigabyte of disk space

2.5" SFF - more capacity and performance per unit of space occupied by a server or storage system in a rack:
• 2 times more storage capacity in a limited space - smaller dimensions and, as a result, a higher capacity density per unit of space (GB/cm3) or per unit of server rack size (GB/Unit)
• higher performance of the storage system in a limited space - smaller dimensions and, as a result, a higher I / O density of the disk subsystem per unit of space (IOPS / cm3) or per server unit in the rack (IOPS / Unit)
• 2 times less power consumption (in all modes) and, as a result, less heat dissipation and cooling costs
, modular and blade servers
• in systems with high performance of the disk subsystem due to a large number of fast hard drives -
• on systems with a large number of RAID groups -
• in systems with maximum reliability of all components -
• in systems with low or limited power consumption -

Not all users of a personal computer purchase a device for productive video games, video rendering or processing 3D models. Quite a lot of people use PCs exclusively for watching videos, storing photos and surfing the Internet.

For such users, the main parameter in the computer will be the amount of internal memory. The more disk space, the more data you can store, which is especially true if you watch videos in 1080p resolution and listen to uncompressed music. Thus, the average size of a movie can be about 20 gigabytes, and the size of one music file, at least 15 megabytes. What can we say about video games that can reach 60 gigabytes uninstalled and more than 100 installed.

A modern computer simply must have at least one terabyte of memory, otherwise, a person will constantly experience the inconvenience associated with a lack of memory. Let's see how to install multiple hard drives in a computer.

What options should the motherboard support?

Of course, no one will purchase a new one (MP) for the sake of a hard drive, however, if the MP is significantly outdated, then you still have to change it.

Previously, hard drives were connected to the MP using the so-called IDE connector.

Distinguishing an IDE connector from a modern SATA connector is quite simple. The outdated connector is connected using a loop of many wires, while 2 thin wires are connected to the SATA connector, one for power and the other for data transfer. If the motherboard does not have a SATA connector, the person will have to replace the motherboard.

When purchasing a motherboard, the buyer should pay attention to the presence of the SATA 3 standard and the number of SATA connectors. In addition, a person should pay attention to ensure that the power supply has enough connectors to power the SATA components.

Hard disk selection

Depending on how many SATA connectors are on the motherboard, a person can purchase so many hard drives. There are motherboards with 12 slots for connecting hard drives, but for such a computer, you will have to purchase the appropriate power supply. Firstly, it must have enough power connectors, and secondly, the power supply must have enough power to run so many components.

If the computer motherboard supports only the SATA 2 type, then the SATA 3 hard drive connected to this interface will operate at a slightly lower speed, limited by the SATA 2 data transfer rate.

When choosing the amount of memory, it is advisable to purchase the most capacious drive possible, especially if the MP is limited to 2 - 3 SATA connectors. However, if the buyer is not limited in funds, he can purchase the maximum capacity hard drive available on the market. Although, of course, it is better not to store all the data on one drive.

As a manufacturer, it is best to purchase those hard drives that are developed by well-known companies such as Toshiba, WD, and Seagate.

A working computer makes a rather noticeable noise, the source of which is the hard drive. The hard drive is especially noisy when reading or writing. Naturally, the more hard drives, the stronger the noise emitted by the computer. Less noisy hard drives with a lower rotation speed of 5400 - 5700 rpm. Unfortunately, the reduced rotation speed negatively affects the overall speed. In addition, if the computer is assembled to order or independently, then you should choose a high-quality case with anti-resonant properties. In order to completely get rid of noise, it is necessary to purchase SSD drives, but their cost is much higher than the cost of classic drives with a lower capacity.

A 250 GB SSD hard drive will cost the same as an ordinary 1 TB hard drive, but its data transfer speed is many times higher than ordinary hard drives. The material "" explains about the units of measurement of information.

Before installing a new component, you must turn off the computer and remove both covers of the system unit. You can access the motherboard from the left side of the case. In front of the case are several compartments "pockets" in which hard drives are installed. The number of "pockets" depends on the form factor of the case. A standard form factor ATX case has an average of about four hard drive bays.

The hard drive placed in the bay is fixed with bolts on both sides of the system unit. Usually, the bolts come with the hard drive.

A securely fixed hard drive makes much less noise. In addition, the hard disk has a movable mechanism, due to which, a poorly fixed part, due to constant vibrations, may be damaged.

After installing the hard drive into the case, it must be connected to the motherboard and power. Both connectors are similar, but it is simply impossible to connect power to the data connector.

Thus, a special SATA cable is connected to the hard drive, the other end of which is connected to the motherboard.

Wires for powering the hard drive are connected directly from the power supply.

After a successful connection, the computer turns on in normal mode. Most often, after turning on, a tool for adding a new device appears on the screen.

If the hard drive is not detected by the system, then you need to enter the menu " Control Panel", Further " system and safety" And " Administration", Then " Computer management”, then “Disk Management” and format the new volume.

After formatting, you should click on the unallocated space with the right mouse button and select " Create a new volume».

Thus, a computer with 2 - 3 hard drives can be considered an ideal option, the smallest of which will be reserved for the operating system (system disk).

The hard disk drives installed in the computer will be displayed in "My Computer" as local drives.

Hello! Please, tell a simple computer user to deal with hard drives and the possibility of their autonomous operation...
The point is the following. It became possible to install a second hard drive on your PC, so that the first one was exclusively for the OS + necessary programs + frequently used files and (documents, technical diagrams, etc.), and the second for home archive (video, photos, films, rarely used files.
I successfully installed the second hard drive myself (the OS sees and maintains it well) ... But there is one problem here. This hard drive should be used from time to time, but it turns out that every time the computer is turned on and off, the OS starts it anyway - and this, after all, affects the resource!
How to make sure that this, let's call it an "archival" hard drive, does not start up unnecessarily? Is it possible?

Nicholas | April 29, 2015, 08:40
" YUM wrote: as a matter of discussion: why not go mechanically? Well, for example, extend the power cord. Take dad / mom out and out of use, just open the pads. The cable, however, will stick out all the same in the "mom", but , I think, beyond the show: "unknown device", OSka will not go ... "

In fact, it was this option that I considered first, and here's why. Now my system unit is (with the wide side) right behind the monitor and the back (free) side (for certain reasons) without a cover (i.e. there is free access to the hardware). The cables of both HDDs are easily accessible. In general, everything is predisposed to removing / inserting connectors. But realizing that everything would quickly become unusable, so I asked myself not a mechanical, but a software switch on and off of the hard drive. Well, it turned out that this, unfortunately, is impossible.
So, YUM, I'll have to follow the path already discussed...

YUM | April 19, 2015, 03:32 pm
in the order of discussion: why not go the mechanical way? Well, for example, lengthen the power cord. Take out dad / mom outside and as unnecessary, just open the pads. The train, however, will stick out all the same in the "mother", but, I think, further than the show: "unknown device", Oska will not go. I remember sticking fans into free blocks on the PSU. For outdoor use. One to blow - on me, the second - in the body. For, it happened, both of us and the computer overheated ... :-)

Nicholas | April 8, 2015, 13:58
Nick Nick, thanks for the reply. From the answers, I realized that the second hard drive integrated into the PC will still be polled by the OS for any of its actions. And therefore, in order to eliminate "unproductive" inclusions and disconnections, it is necessary to exclude it from the direction of one OS. That is, it is either a PC with two motherboards (and different OS), or a second PC, or an external hard drive, or a NAS ...

Nick Nick | April 7, 2015, 14:47
I did it this way, in the system unit there is a 500 gb disk divided into two partitions on one partition, the system on the other, downloaded movies, etc. In a beautiful plastic case called an external HDD box, there is a second (standing right on the table) hard drive also for 500. Moreover, it has an autonomous power supply switch on the case. There are photos and archives on it, and it is connected with a switch when needed, and when not needed, it is turned off by a switch on the body. It is connected to a USB computer (comes with a box in the kit). The system sees the disk as a large flash. I took this box and watch photos and videos DVD or wherever there is USB.

Nicholas | April 7, 2015, 08:19
Nick, maybe you are right about something. But then again, I do not need a backup disk (did I name it correctly?), which will be stored in a cabinet.
There were 2 hard drives available (500 GB and 2 TB). On the first one, I placed the OS with accompanying programs (which are not yet installed all the necessary ones). By the way, as Dima Svinkin mentioned, the system disk was divided into two logical ones - for the OS itself and for different files needed in everyday work. And the second HDD (2 TB) is gradually filled with "house stuff" (photos, videos, films, music, rarely used documents, drawings, etc.).

As a result, after turning on the PC, after a while (as you mentioned, Nick) the "dvuhterrabyte" "falls asleep", I don't even know when this happens. On the one hand, this is good - the hard drive is not used, and on the other hand, the problem I describe arises.
Nick, I can’t buy an external drive yet (especially now they are very expensive, and there are already 2 TB available). It's just that I have the opportunity to get a small system unit - I'll probably have to "dance" from this option.
By the way, Nick, I'm certainly not an IT specialist, but all the same, everywhere it is said that the hard drive should be treated with care, including for him it's better to "spin" all day than to start and stop.

So, in summary, we can say the following:
1) separate management on one computer, with one OS, two physical hard drives (without good system knowledge and access to BIOS) is almost impossible.
2) to solve the problem I am describing, it is proposed to either physically turn off the second HDD (which is unrealistic), or use an external HDD, or you can use the second system unit of a small form factor.
Is everything right?

Nick | April 6, 2015, 22:47
For Nikolai: "professor" on one of the IT sites - advised you correctly. It is best to have 2 disks in the system. But they are used for something completely different. For example, only the system is on one disk. And if the system crashes or you need to restore it from a backup image six months ago, then your current documents will not be affected in any way, because. they are on a different drive. You won't lose anything. Or you need to check for errors or defragment the system disk - the operation will be performed much faster in time on a small system disk (where only the system) than on a huge shared disk, where in addition to the system there is a bunch of your documents, pictures, videos, etc. In short , 2 disks are used for data spacing - and this is necessary for the convenience of system maintenance.

I don't know what you are afraid of switching disks on and off. There is nothing to worry about, modern disks are designed for this, they can even turn off and fall asleep if they are not accessed for a long time.

Well, if you want to turn off the drive yourself, then buy an external drive. For example, I use an external USB-3 drive. It works quickly to turn it off - you just need to remove the connector with a cord from the computer's socket (it is inserted into the USB flash drive connector).

Nicholas | April 6, 2015, 20:54
Thanks to everyone who answered my question. A separate "curtsey" for Alek55sandr5 - it seems that you immediately "caught" the essence of the issue.
Now it becomes clear that if two (3.4) hard drives are connected to one OS (which the system "sees" as separate physical drives), then every time you turn it on, turn it off or reboot, the system will always start them all (which, of course, reduces their resource, because for a hard drive one of the most difficult modes is start-up, when the spindle spins "pancakes" Right?)
It is strange that at one time, some "professor" on one of the IT sites, "advised" to have two separate hard drives in his PC (and not in some kind of ride array, namely two separate physical ones - one for OS and related programs, and another for home videos, photos, books, document archives and other relatively rarely used files). So I "bought" this "call".
That is, for me it would be the right decision: a separate small-sized system unit, from which to make something like a NAS and connect it as needed? This is the only way I can save the second hard drive from unnecessary inclusions. Right?

Dmitry | April 6, 2015, 10:59 am
Put there a swap file and a folder for temporary files. The disc will give back.

Svinkin Dima | April 5, 2015, 04:43 PM
Strongly disagree with you! A home archive must be created and stored on an external hard drive. What size is your system (physical disk)? For OS + various programs, 100-150 GB is usually enough, and for many users the system (logical) one is even several times smaller than these sizes. If you had one physical disk in your computer with a nominal size of 320 GB or more, then it is unreasonable to define this entire volume under OS + programs. It needs to be divided into two partitions (two logical drives) C:\ and D:\. Disk C is the system drive, and on drive D: \ you should place folders for temporary files of all programs, folders for downloading from the Internet, folders for saving files created in different programs and a temporary archive of the most popular files. Any extra physical device in a computer can turn into a headache at any time - this is a practice.

Alek55sandr5 | April 5, 2015, 15:50
As far as I know, unfortunately it is impossible to completely turn off the hard drive if it is connected to a PC. Each time you start the operating system, the hard drive will boot with it and its resource will slowly wear out. You can copy some files to this hard drive and remove the connected cables from its connector. Thus, it will be completely disabled and its resource will be larger. But of course, if this option suits you.

Good afternoon.

I must state one thing to you - laptops, after all, have become much more popular than ordinary PCs. And there are a number of explanations for this: it takes up less space, it is convenient to carry, everything is immediately included in the kit (and you need to buy a webcam, speakers, UPS, etc. for a PC), and they have become more than affordable at a price.

Yes, performance is somewhat lower, but very many people don’t need it: the Internet, office programs, a browser, 2-3 games (moreover, most often some old ones) are the most popular set of tasks for a home computer.

Most often, as standard, a laptop is equipped with one hard drive (500-1000GB today). Sometimes it is not enough, and you need to install 2 hard drives (all the more this topic is relevant if you replaced the HDD with an SSD (and they still do not have a lot of memory) and one SSD is too little for you ...).

2 drives in a laptop - installation options (connection)

1) Connecting a hard drive through an adapter (instead of a drive)

Relatively recently, special "adapters" appeared on the market. They allow you to install a second drive in a laptop, instead of an optical drive. In English, this adapter is called: "HDD Caddy for Laptop Notebook" (by the way, you can buy it, for example, in various ones).

True, they cannot always "perfectly" sit in the laptop case (it happens that they are somewhat buried in it and the appearance of the device is lost).

Instructions for installing a second drive in a laptop using an adapter:

Rice. 1. An adapter that is installed instead of a drive in a laptop (Universal 12.7mm SATA to SATA 2nd Aluminum Hard Disk Drive HDD Caddy for Laptop Notebook)

Another important point - pay attention to the fact that these adapters can be different in thickness! You need the same thickness as your drive. The most common thicknesses are 12.7 mm and 9.5 mm (Fig. 1 shows the 12.7 mm version).

The bottom line is that if you have a 9.5 mm thick drive, and you buy a thicker "adapter", you won't be able to install it!

How to find out how thick your drive is?

Option 1. Get the drive out of the laptop and measure it with a compass rod (in extreme cases, a ruler). By the way, on the sticker (which is glued in most cases) the device often indicates its dimensions.

Option 2. Download one of the utilities for determining the characteristics of your computer (link to the article:), then you will find out the exact model of your drive in it. Well, according to the exact model, you can always find a description of the device with its dimensions on the Internet.

2) Is there another HDD bay in the laptop?

Some laptop models (for example, Pavilion dv8000z), especially large ones (with a 17-inch monitor or more), can be equipped with 2 hard drives - i.e. they have a design for connecting two hard drives. On sale, they can be one tough ...

But it must be said that there are actually not many such models. They began to appear relatively recently. By the way, one more disk can be inserted into such a laptop instead of a disk drive (that is, it will potentially be possible to use as many as 3 disks!).

Rice. 3. Pavilion dv8000z laptop (note that the laptop has 2 hard drives)

3) Connecting a second hard drive via USB

The hard drive can be connected not only through the SATA port, by installing the drive inside the laptop, but also through the USB port. To do this, however, you will have to buy a special Box (box, box * - see Fig. 4). Its cost is about 300-500 rubles. (depending on where you get it).

Pros: reasonable price, you can quickly connect any drive, pretty good speed (20-30 MB / s), easy to carry, protects the hard drive from shocks and shocks (albeit slightly).

Cons: when connected, there will be extra wires on the table (if the laptop is often moved from place to place, this option will obviously not work).

Rice. 4. Box (Box with English translated as a box) for connecting a hard SATA 2.5 disk to a computer USB port

This concludes this short article. For constructive criticism and additions - I will be grateful. Have a nice day everyone 🙂