All RAM in windows 7 is displayed. How to use all installed memory in the simplest ways? PAE Mode Limitations

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Exist whole line programs that are inherently charlatan. All of them promise a miraculous increase in computer speed by freeing up space in the computer's RAM. To understand why this is useless and even harmful, first you need to figure out - what is RAM in general?

What is RAM and why is it needed?

RAM (or RAM - Random Access Memory, or RAM - ABOUToperative Zreminiscent Havedevice) - volatile memory used to temporarily store instructions and data required for calculations that the processor (or processors) of the computer does. More precisely and in detail about this is described in Wikipedia, and I will focus on the actual problem of free space in RAM.

Note: I am speaking in the most simplified way, omitting many terms and features, leaving only the very essence required in the context of my note.

RAM is needed by the processor for quick data access that hDD can not provide in any way. Therefore, at startup, the program is loaded into rAM - this is the only way a computer can do calculations by sending data to the processor from RAM and back.

In Windows, running programs can be physically located not only "in RAM cards", but also on the hard disk in a file pagefile.sys. This file is called a "swap file" or "swap" (from the English. Swap).

The idea is this: if a program takes up a lot of memory, part of it is swapped out to the hard disk, freeing up "living space" for other programs, and if necessary, the data is loaded back into RAM.

Problemis that the difference in speed between RAM and hard drive huge... This can be clearly demonstrated as follows:

So that only unnecessary data is dumped into the paging file, the Memory Manager works in Windows. It works quite successfully, thanks to which a computer with 512 MB of RAM can run programs that take up more than a gigabyte of memory. Typical example - modern versions Adobe Photoshop, 3DS Max and many other programs for complex calculations. Of course, with such a small amount of RAM, programs will strong slow down, but work in them at least, but it is possible.

What do memory optimizers do?

As an analogy, medications for relieving symptoms do not treat the cause, only relieve the symptoms. If a person has the flu, getting rid of the common cold will not cure them. If the computer slows down and there is not enough free memory, it slows down not because of occupied memory, but because of an overly resource-intensive program or, for example, overheating.

All optimizers are required show the amount of free space in RAM. And often with red letters and warnings that this negatively affects the speed of the computer. Which is actually not true. If the program needs all the RAM, it means that it is required for the case (calculations) and work quicklyshe will only be if she is given as many places as she asks for.

A typical example of programs that require large amounts of RAM are games. If the game requires 2 gigabytes of RAM, nothing can be done about it. Without the required amount of RAM, it will be problematic to play due to the low frame rate - the game will slow down due to the fact that some of the data will be located on a slow paging file. RAM optimizers create the same negative effect - after freeing the memory, programs are allocated less memory than they need, which is why, again, "brakes" begin.

Note # 1: I am not suggesting that the frame rate in games is directly related to the amount of RAM. By installing more RAM in the computer, it will be possible to increase performance only in those programs where the amount of RAM is really important, without regard to other more important parameters: processor frequency, video card characteristics, RAM frequency, hard disk speed, etc.

Note # 2: Errors occur with programs under common name « memory leak“When a program“ grows ”for no reason and occupies all memory unnecessarily, but in this case it is necessary to require the developers of this program to fix the error, and not to free the memory by optimizers.

How memory optimizers work

Memory optimization programs (they may have different names - SuperRAM, FreeMemory, Memory Management SuperProMegaEdition, etc.) can free memory in several ways, but they are all tied to the principle of tricking the Windows Memory Manager:

1. The program calls special function EmptyWorkingSet (), which forces all programs to unload themselves into the swap file as much as possible.
2. The program begins to grow uncontrollably in memory, telling the Windows Memory Manager that it needs it for the case (I say in metaphors, but in fact this is the case), as a result of which the Memory Manager throws as many programs as possible on the hard disk into a file swap.

The bottom line is always the same: programs start to slow down, but the number of free space in the RAM is green and the memory optimization program says that everything is fine. As a result, the user is happy, opens a window with his favorite program and ... waiting. Because his favorite program starts slow down strongly. This will continue until the program returns "itself" to RAM from the paging file. As a result, the RAM fills up again, the free space indicator again reports that the memory is busy, the user gets angry, starts clearing the memory and everything happens in the second (third, fifth, tenth) circle.

The opposite effect - so that the program takes up all the RAM ostensibly for fast work - it will not be possible to achieve. I used the word "allegedly" because in the ideal case (when there is enough memory) programs take as much memory as they need and it is impossible to interfere with this process... If you interfere with the process, you will get the brakes caused by frequent access to the paging file.

Another sad point: memory optimizers cannot unload from RAM unnecessary programs... We define their "unnecessary" ourselves, in the computer everything is arranged differently. All programs are unloaded to the swap file indiscriminately.

Conclusion number 1:freeing up RAM by optimizers is only harmful and slows down performance.

Conclusion number 2: you cannot judge the speed of a program by how much space it takes up in RAM.

Conclusion number 3: if a program takes up a lot of memory space, it means that it operates with large amounts of data. It is possible to help her "think" faster only by increasing the amount of RAM, ie. by putting more RAM cards in the computer. But it won't help if the rest of the PC specs don't meet the requirements.

Not to be unfounded, here is a link to similar conclusions explaining the operation of the Windows Memory Manager: here.

How should memory be optimized?

The most obvious way to improve computer performance is to close unnecessary programs. The second is to install more RAM strips (boards) so that the programs “feel more at ease” and run faster. Other ways to speed up your computer, directly related to RAM, no.

I repeat: memory optimizers are nonsensein order to make money from gullible users. The same stupidity is the adjustment “ hidden settings memory "in Windows, because everything is already configured most optimally there after testing on a large number of computers. There are specific moments, but this does not apply to home computers.

About free RAM in Windows Vista, 7, 8, 10

On the forums, I often see outraged shouts (I quote): “ I installed Windows 7 (8, 10), looked at the Task Manager, and it says that one and a half gigabytes or all the RAM is occupied! Windows 7 (8, 10) is eating a lot of memory!»

In fact, this is not at all the case and there is no reason to be indignant. Quite the opposite: in modern operating systems, free memory is allocated for the cache. This is mainly due to the SuperFetch feature. Thanks to the cache, programs start faster,since instead of accessing the hard disk, data is loaded from RAM (see the picture above, the difference in speed work hard disk and RAM is written in bold). If some program needs more RAM - cache instantly will reduce its size, giving way to it. Read more about this on Habrahabr.

Conclusions:

1. There is no need to clear the memory because each byte of the volume is used to the maximum effectively.
2. Forget memory optimizers - they don't optimize anything, interfering with the cache and other Windows functions.
3. If a lot of RAM is occupied immediately after turning on the computer, this is absolutely normal and is not the reason slow work programs. Of course, if autoload is crammed with a dozen or so programs that occupy this very memory, at the same time loading the processor and using the hard disk,it will be necessary to slow down. You need to deal with such programs by deleting them or removing them from startup, and not clearing memory with optimizers.

There is also a myth that when using Windows Vista, 7, 8 and 10, cache interferes with programs. Allegedly "when a program needs more RAM, it turns out that it is clogged with cache, there are brakes." This is actually not true. The cash disappears instantly and program at once the required amount of RAM becomes available.

Resize, move, or disable the paging file

Also quite common, in some way harmful, advice. There is a good article about this on Habrahabr. I will only give the most important conclusions of that article, adding my own, from personal experience:

1. There is little point in changing the paging file size. Theoretically, ideally, you should set the paging file size to no more than that required by running programs, but the problem is that even if you use the same programs of the same versions day after day, situations are different (you can run in browser one tab, or you can a hundred, each with an open game in Flash) and the requirements for available memory will be different - the estimated "ideal" paging file size will vary from minute to minute. Therefore, it makes no sense to change the size of the paging file, since the “ideal size” of the paging file changes constantly. It's easier to leave the size that the system has determined and not fool yourself.
2. If you disable the paging file on the system partition (while the paging file can be used on other partitions), memory dump will not work on BSOD errors. Therefore, if the system displays “ blue screen death ", to identify the cause of the failure, you will first have to enable the paging file on the system partition, then wait for the failure to recur. There is only one situation when it is advisable to disable the paging file on system disk (to be deprived of the diagnostic capability) and turn it on on the other - if two or more physical hard drive... Moving the paging file to another physical disk can reduce the amount of slowdowns due to load balancing across disks.
3. Disabling the paging file (full, i.e. on all disks) will cause problems and crashes of resource-intensive programs. Believe it or not, even now, with an average of 16GB of RAM installed in your home PC, there are programs that need more. Personally, I ran into problems when rendering complex scenes using V-Ray and when working in the GIMP program - these programs are quite gluttonous in terms of available memory and close when there is not enough memory.
   Note: it is obvious that programs usually do not write data to the paging file themselves, the OS does it for them (but there are exceptions). However, a disabled paging file cannot be considered part of normal computer operating mode.
4. Moving the paging file to a RAM disk (very fast virtual diskin RAM) impractical.
   First of all, and this is the most important thing, when windows startup The RAM disk can be initialized later than the moment when the system needs the paging file. Because of this, anything can happen - from BSOD to spontaneous system slowdowns (I ran into the above when testing this idea).
   Secondly, the size of such a paging file will be small - the memory is not rubber. There is a choice - either a lack of RAM with a large paging file in memory, or program glitches when there is not enough space in a small paging file. There is no golden mean, tk. a computer can perform completely different tasks.
   An exception when you can create a large swap file on a RAM disk - if you have 16 GB of RAM or more. However, with this amount of RAM, the paging file is almost never used, it makes no sense to keep it in RAM.
   Thirdly, it's just pointless, because the swap is needed to expand virtual memory at the expense hard disk or SSD.

Clearing the paging file

In the swap file pagefile.sys a variety of confidential information can be stored - for example, pictures from recently opened pages in the browser. it normal processdue to the peculiarities of the work of programs in Windows. Optionally, you can enable the cleaning of the paging file when the computer is turned off. However, this tweak will not improve performance in any way; on the contrary, it will seriously slow down the shutdown and restart of the computer.

If you not work with confidential data, better do not include pagefile.sys cleanup.

More than 4 GB of RAM available in Windows

The Internet is literally inundated with the reasoning of users about why 3.5 GB of RAM is available in bit Windows instead of, for example, the installed 4 GB. Many theories, myths, legends were invented. For example, it is believed that this is a limitation made by Microsoft that can be removed. In fact, this is partly true - there really is a forced restriction. Only you cannot remove it. This is due to the fact that in 32-bit systems, drivers and programs can be unstable when the system uses more than four gigabytes of RAM. For 64-bit Windows driver more thoroughly testing, the above limitation is not there.

In 32-bit Windows, only 4 GB of RAM is available, in 64-bit there is no such limitation and much more RAM is available - up to 192 GB.

But it's not that simple. Windows 7 Initial (Starter) (and its Vista counterpart) doesn't see more than 2GB of RAM. This is also a limitation, but not because of unstable software. The fact is that Windows 7 Starter is distributed exclusively on low-power netbooks, in fact, almost free, so it was necessary to distance it from more expensive editions: Home Basic, Home Extended, Maximum, etc. Some of the limitations of Windows 7 Starter can be removed, but not the limitation on two gigabytes of RAM.

As for the rest of the 32-bit editions of Windows XP, Vista, 7 and Windows 8/10: in practice, even less is available to the user - 3.5 GB. The thing is that drivers also have their own addresses, which deprive programs Windows access to a piece of memory of 512 megabytes. There is a patch that allows you to "push" such addresses beyond four gigabytes so that the system begins to use all 4 GB of RAM, but this practically makes no sense:

• As I wrote above, drivers and programs will not be able to work correctly after such a patch, so the system may start to freeze, give errors, i.e. behave unpredictably.
• Even if the computer will have 8, 16, 32 GB or more RAM cards installed, this will not help in any way to use them in the 32-bit mode of the operating system.

What's the point of having an extra 512 MB of RAM available if the system becomes unstable? Here's a good example. You still have to install 64-bit Windows.

Just because 4GB of RAM is visible does not mean that it can be used effectively. The problem is that 32-bit Windows cannot correctly allocate more than 2 GB of physical RAM to a process (program). Many people forget about this - and in vain. It doesn't matter how much RAM is in the computer if the program cannot be given more than 2 GB of RAM. Example: if a user works in 32-bit Windows with Photoshop on a computer with 4 GB of RAM - Photoshop will be able to use only two gigabytes maximum, the rest of the data will be thrown into the paging file and will slow down. It's the same with games.

In fact, only in a 64-bit operating system can programs use the full potential of RAM with a volume of more than two gigabytes. And that's not all, but only designed to use more than 2 GB of RAM. Again, the situation can be corrected using the appropriate patches in 32-bit Windows, but this does not work with all programs. I repeat: only 64-bit Windows and 64-bit programs running in it are the only way to use the full potential of a large amount of RAM.

Meanwhile, the situation is different with server versions of Windows: much larger amounts of RAM are available there, even in 32-bit versions of the OS. Why this happens is explained in the article Breaking the Windows Boundaries: Physical Memory by Mark Russinovich.

Summing up

• You cannot use RAM optimizers.
• Touching the memory settings is the same, even if the program has a lot of prompts that give a sense of control over the situation.
• Free RAM in Windows Vista/ 7/8/10 is used for the good, it is better not to touch this functionality - everything works well, practically nothing can be improved.
• If your computer slows down, then this probably not because of the occupied memory (it is occupied by the useful cache), but because of, or a large amount running programs or one program that “takes” everything for itself.

In this article we will figure out how to remove the 4 GB memory limitation on 32 bit versions of Windows 8 and Windows 8.1, and use all the RAM available on the computer.

Most windows users convinced that 32 bit Microsoft OS does not support more than 4GB of RAM... Thus, the maximum memory available in Windows 8 / 8.1 x86 is 4 GB. And taking into account the fact that Windows reserves a part of the memory for its own needs and requirements peripherals) most often for a video card), end user usually about 3-3.5 GB of memory are available for use.

At first glance, everything is logical - the addressing limit for a 32-bit address bus is the same 4 GB. In all official microsoft documents specifies exactly this maximum memory size supported in all client versions of the x86 system. Although actually Microsoft is misleading everyone a little.

What is PAE and why is it needed

PAE (Physical Address Extension - extension of physical addressing) - this option x86 processor, allowing it to access to more than 4 GB of physical memory... We will not go deep into the technical details of PAE technology, just note that this technology has been supported by all processors and directly in Windows OS for quite some time.

So for example the 32 bit version Windows Serverrunning on an x86 processor can use PAE to access the entire system RAM (up to 64GB or up to 128GB depending on processor generation).

Moreover, support for PAE mode in the Windows kernel has been available since Windows XP. It's just that by default PAE is available only in server operating systems, and in client Windows operating systems, although this mode is available, it is disabled.

Note... PAE can only be used on 32-bit versions of Windows running on x86-compatible processors.

Limitations of PAE Mode

• PAE does not expand the virtual address space of each process. Every process running on a 32-bit system is still limited to 4 GB of address space.

  Advice... PAE will not help increase the amount of memory available for a resource-intensive application (such as a graphics or video editor). If there is such a need, it is better to upgrade to a 64-bit OS.

• When using PAE, a slight decrease in system performance should be noted due to a decrease in the speed of access to memory, caused by the overhead of switching mapped pages in memory
• Some device drivers may not work correctly in a 36-bit address space.

So, we can conclude that the upper limit of available physical memory in 32-bit versions of Windows is programmatically limited at the OS kernel level. And if there is software restriction, that means it can be bypassed! How to enable PAE mode in 32 bit Windows 8.1 and use all available RAM.

Patch enabling PAE to use all RAM on Windows 8 / 8.1 x86

Enable PAE Mode in Windows 8 (Windows 8.1) regular means will not work (for this you have to manually edit the kernel file ntoskrnl.exe and re-sign it in a HEX editor). The easiest way is to use a ready-made patch PatchPae2which is written by the enthusiast Wen Jia Liu. You can download the patch PatchPae2. (the archive contains the patcher itself - PatchPae2.exe, its source codes and necessary instructions).

The patch is a small command line utility that allows you to modify the kernel files of 32 bit windows versions in order to activate PAE mode, which allows you to use more than 4 GB of RAM (up to 128 GB of memory).

PatchPae2 will work with the following operating systems:

• Windows Vista SP2
• Windows 7 / Windows 7 SP1
• Windows 8 / Windows 8.1

Note... Before installing a patch, it is recommended to disable optimizers and RAM drivers in order to prevent conflicts. They can be activated after applying the patch and booting the system in PAE mode.

Installing PAE - patch in Windows 8 / 8.1

Attention. This instruction can only be used for 32-bit versions of Windows 8 and Windows 8.1, the procedure is slightly different for previous Microsoft operating systems! Be careful!

Note. At any time, the user, after rebooting, can switch from PAE mode to normal mode in the boot menu, or vice versa.

Important! After installing the patch, you need to be especially careful when installing updates windows security... Because some windows updates sometimes they also contain updates for the kernel, after their installation it is necessary to update the PAE kernel: PatchPae2.exe -type kernel -o ntoskrnx.exe ntoskrnl.exe

In addition, the problems described and may occur.

Removing the PAE patch

To remove the PAE patch from the system, you must:

1. Remove matching entry from boot menu (the easiest way to do this is with msconfig)
2. Delete files ntoskrnx.exe and winloadp.exe in the catalog % Windir% \\ System32.

The patch does not make any other changes to the system.

All personal pc users are striving to increase their RAM. If you are going to install an additional bar, it can put your plans, as the computer may simply not see it. So why is not all the RAM available in different versions Windows?
The computer will not see the RAM for several reasons. The capacity of the system can play a big role. A computer running a 32-bit operating system won't see more than 3GB of RAM because that's how it works. To fix this problem, you need to install a 64-bit operating system.
A situation may arise that the system really shows the amount of RAM that it should be, but it is available in less memory. This is due to the fact that the memory is reserved for the built-in video card, but if there is a discrete one, this problem will not be detected. But still, you should make sure of this and check whether it is enabled in the BIOS or not and how much memory it is currently using.
Also, if you select an option such as "Maximum memory", you will not be able to take full advantage of it. It is possible to check this with the system configuration.

Probable problems

If this parameter is not found, the BIOS should be updated. There is also a possibility that this function was not implemented during the production of the motherboard. In this case, the best option would be to replace old version to a newer one that will support unlocking the RAM to use more than 4GB.

Outdated hardware can also be a hindrance. Older motherboards may not see more than 4GB. To do this, you need to look at the characteristics of the motherboard itself and find out about the maximum amount of memory that it can support.

It is also possible that if the strap is new, you can try to install the RAM in different slots, this can solve the problem. Maybe the rearrangement will help the system see them.
If these methods did not help you solve the problem, then consider the following options that may help you.
Wrong bIOS setup could be to blame too.

Enable memory reallocation

Check the BIOS to see if memory remapping is enabled in its options. If you reallocate memory, then for windows its huge amount can become available. It is up to the supplier of the hardware how to call the function that will be responsible for reallocating memory. It may have names such as memory expansion, memory reallocation, or other similar names. But also exclude the fact that such a function as memory reallocation may not be available on a computer.

Resize AGP Video Hardware Using BIOS Options

It is required to find out about the allocated memory specifically for AGP video equipment. The system shares this memory with the video adapter, which is used to render textures and renders. BIOS settings help in adjusting the size of the video equipment. Its size is usually 32,64,128 or is set automatically. Then you should restart your computer and check the amount of RAM.

Updated: 13.04.2019 Published: 15.06.2018

Description

The system detects less RAM than is installed in the computer.

Or not all memory is available to the system:

Also, not all of its volume can be determined in the BIOS (more often, only half).

Cause

1. Part of the memory is taken up by the built-in video card.
2. Edition or bitness limit of the operating system.
3. Software limitation.
4. System memory reservation.
5. Defective RAM.
6. Processor limitation.
7. BIOS error or the need to update it.
8. Maximum volume limit that supports motherboard.
9. The motherboard does not support one of the memory modules.

Decision

1. Using the built-in video card

This problem is characterized by insignificant memory allocation for the video adapter. In this case, we will observe a slight decrease in available memory, for example:

If we want the built-in video card to consume less memory, go to BIOS / UEFI and find one of the parameters:

• Share Memory Size
• Onboard VGA Frame Buffer
• Display Cache Window Size
• On-Chip Video Window Size
• Onboard Video Memory Size
• Internal Graphic Mode Select
• Integrated Graphics Share Memory

* in different versions BIOS they can be called differently. It is also possible that other parameters can be used - in this case, you need to study the documentation for the motherboard or use a search engine.

After we change the amount of memory reserved for the video systems needed:

2. Operating system limits

Different editions of Windows have a limit on the maximum amount of memory used.

a) All 32-bit versions can use a maximum of 3.25 GB of RAM. This architectural limitation is the limit that a 32-bit system is capable of. The picture will be something like this:

To use more than 3 GB of memory, you need to reinstall the system to the 64-bit version.

b) Windows editions also have limitations. For example, Windows 10 Home 64 bits will allow you to use 128 GB, and Windows 10 Pro x64 - 512 GB. With Windows 7, the situation is worse - the home basic edition will only allow you to use 8 GB, and the initial one, only 2 GB.

More details in the tables:

If our problem is related to the revision limit, we need to update the system or reinstall it.

3. Software limitation

The limitation can be set in the system. To remove it, open command line and enter the command msconfig - the "System Configuration" window will open (you can also use windows search by window name).

In the window that opens, go to the tab and click on Extra options:

We check that the box is not checked Maximum memory:

4. Setting up the basic I / O system

In order for the computer to use all the memory, in some cases, it may be necessary to configure the BIOS / UEFI:

5. The maximum volume that the motherboard supports

It is necessary to check what the maximum volume can be seen by the motherboard itself. To do this, you should use the instructions - it comes in the kit, and you can also download it on the manufacturer's website. Also, similar information can be found on some online stores:

6. Defective memory module

In the event of a memory failure, the system and the BIOS will not display its entire volume (usually only half). For example, if 16 GB is inserted into the computer (2 strips of 8 GB each), we will see only 8.

In this case, you can try to pull out and reinsert the memory sticks (you can blow them out a little from dust). Also, the planks can be swapped. You can also try cleaning the contacts (a regular eraser will do). Some laptops or all-in-ones have a separate plug, opening which you can get to the memory modules, otherwise you need to disassemble the computer completely.

If this does not help, we perform a memory test. In the case when the test also shows part of the memory, we try to pull out both strips and insert them one at a time - if the computer does not turn on with one of them, this faulty strip needs to be replaced, if the computer starts up with all the strips, perhaps we are dealing with a problem BIOS (step below).

7. Processor limitations

Each processor has its own limit to support the maximum amount of RAM. You need to go to the developer's official website and check the maximum volume supported by our processor.

8. Installing the driver for the chipset

Updating or reinstalling the driver may also help resolve the issue. To do this, we determine the manufacturer and model of the motherboard, go to the manufacturer's website, find the page specific model and download the driver for the chipset. Install the downloaded driver and restart your computer.

Also, the driver can be installed in a semi-automatic mode using the DriverHub program.

9. Problem with BIOS / UEFI

Since BIOS / UEFI is responsible for collecting information about the computer, the problem may occur at the initial stage of turning on the PC.

First, let's try to reset the settings. To do this, disconnect the computer from the power source and take out the battery for 20 minutes (the first time you can try, seconds, for 10). If this does not help, update the BIOS.

10. Support for the module from the motherboard

If the memory was purchased in addition, and it differs from the second strip, you need to make sure that the motherboard supports the new module.

This can be done on the official website of the motherboard manufacturer - go to the support section and find the compatibility sheet. It is necessary to find the purchased memory among the list of equipment.

11. Windows license limitation

The systems that come with computers use a strict licensing policy that restricts hardware replacement. This can lead to a situation where when adding memory, it will not be recognized as a whole.

In this case, you need to reinstall the system. In this case, a simple reinstallation over the existing system will not help - only full formatting system partition with the installation of a new Windows.

12. Rearranging memory modules

Sometimes, rearranging memory modules by sisters helps. We just disassemble the computer, take out the modules and swap them.

13. Cleaning modules with an eraser

If the problem appeared by itself, you can try to remove the memory modules from the motherboard and clean their contacts with an eraser. Then we blow through the connectors on the motherboard and insert the memory into place.

Increasing the range of RAM is one of the easiest methods to improve PC performance. However, many users often face the following problem: after adding memory operating system reports that she is not available to her. For example, after increasing the volume to 8 GB, Windows only sees 4 GB. Such problems can be caused by hardware or software reasons.

A 32-bit operating system is used

When using Windows 7, 8, XP, Vista on the 32-bit version, maximum amountrAM that they are able to recognize. 32's bit versions are strongly limited in scope of recognition. For this reason, users with more RAM should use the 64-bit version, otherwise they won't be able to use it in full.

In order to find out your version of the operating system, you need to go to control Panel and select the item " System". In the column " Installed memory"Shows the size of the installed RAM, and in brackets indicates how much of it can be used. The number of bits of the operating system is displayed next to it.

Windows version does not support this amount of memory

The operating system may not recognize all of the RAM due to version limitations. Each edition of Windows has its own limitations, for example:

• 7 starter - 2 GB;
• 7 home basic - 8 GB (including for the 64-bit version).

A complete list of Windows editions that have a corresponding limitation can be found on the Microsoft website.

If this problem occurs with a 64-bit windows system 10, you can fix the situation by reset BIOS settings.

Memory reserved by video card or other hardware

A common option is a situation where part of the random access memory reserved for its work other equipment. Most often it is used by the integrated graphics card. In order to check how much RAM is used by other equipment, you need to go to the window " System". If the memory is really reserved by other devices, 2 values \u200b\u200bwill be shown in the corresponding column: the installed volume and the volume available for use, which is displayed in brackets. The difference between these indicators shows the amount that other devices take away.

This option is possible if the PC has a video adapter that does not have its own video memory. In this case, the system automatically allocates RAM to it at the BIOS level. Also often it can reserve network adapter.

The motherboard does not support this amount of RAM

A motherboard may also be limited by the amount of computer memory installed in it. This is manifested in the fact that after successful installation of modules and startup, the board cannot use its entire volume.

In order to make sure that this is exactly the reason, you need to enter the BIOS and read information about the supported volumewhich will be displayed on the first screen. In order to prevent such a situation, you should carefully study the specification of the motherboard before installing it.

RAM strips are installed incorrectly

If the motherboard supports the entire amount of RAM, and it is not displayed in the BIOS, then the reason may lie in its incorrect installation... It is possible that the contacts are poorly connected to each other. This problem is solved very simply: just take out the board and plug it in, or swap slots or shuffle the strips.

RAM damage

The most difficult problem is damage to the RAM strip itself. You can damage it in operation process or installation, in addition, the marriage can be production. In order to ascertain the damage, you should test all planks alternately in one port. After each shift, you should turn off the computer and check in the BIOS whether the computer sees this bar. In addition, you can check each bar separately or all together for another computer... To get out of this situation, it is necessary to repair or replace the device.