How Much RAM Should Be Installed in Your Windows Computer?

How Much RAM Should Be Installed in Your Windows Computer?

One of the main considerations that is taken when purchasing a new Windows computer is how much RAM should the computer contain? As with everything else in technology the answer is usually “it depends.” Most computers sold today seem to have at least 4GB of RAM, which is more than enough for most people. For those that are into video or photo editing, then having more will definitely help.

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When it comes to gaming, which seems to be pushing the graphics technology, it may not matter if you have 4 GB of RAM or 12 GB. The reason comes down to how the actual game is developed and the operating system. As with many things in life, there are limits that will have an effect on how much RAM you may actually need, and be using.

How Much RAM?

Virtual Address Space

On a Windows system, even if you have 24 GB of memory installed, an application may not be able to utilize all of that memory. In fact, depending on your system, a single application may not be able to use more than 2 GB of memory. The reason has to do with the Virtual Address Space of a process.

The Virtual Address Space is the set of virtual memory addresses (a combination of physical RAM and the pagefile) that a single process can use. The virtual memory address space for a process is private, which means it can’t be used by another process.

The limits for a process’ virtual address space are shown in the table below:

Memory Type X86 Limit 64-bit Limit
32-bit Process 2 GB


2 GB with IMAGE_FILE_LARGE_ADDRESS_AWARE cleared (default)


64-bit Process Not applicable With IMAGE_FILE_LARGE_ADDRESS_AWARE set (default):

  • x64: 8 TB
  • Intel Itanium-based systems: 7 TB


As you can see the limits on a 32-bit process running on a 32-bit system is 2 GB. This means that each process can access more than 2 GB for its virtual address space. For a 64-bit application running on a 64-bit computer, the virtual address space for each process increases to 8 TB.

Knowing the virtual address space for an application is important – especially for games. Some games allow you to install mods (modifications that can change the look and playability of the game), and with too many mods it could cause the game to go beyond the limits of the virtual address space. When this happens the game will crash.

Windows Memory Limitations

Outside of the virtual address space, which is not how much physical RAM can be used by a process, is the fact that each version of Windows has a limit to the amount of RAM it can utilize. The memory limit for each version of Windows depends on whether the computer is 32-bit or 64-bit.

The following table shows the memory limits for the Windows versions that are commonly found on home computers:

Version X86 Limit 64-bit Limit
Windows 7 Ultimate 4 GB 192 GB
Windows 7 Professional 4 GB 192 GB
Windows 7 Home Premium 4 GB 16 GB
Windows 7 Home Basic 4 GB 8 GB
Vista Ultimate 4 GB 128 GB
Vista Home Premium 4 GB 16 GB
Vista Home Basic 4 GB 8 GB
Windows XP 4 GB 128 GB

The above table doesn’t list all versions of the Windows operating systems, but I just wanted to show the more commonly installed versions on a home computer.

As you can see from the above table, each version of the Windows operating system has a memory limit. On 32-bit computers, the limit is 4 GB. For 64-bit systems, the limit is dependent on the version of the operating system. For the most part, the 64-bit memory limit probably exceeds the total RAM installed on most computers.

Now what does this have to do with how much RAM you will need installed? Well, if you decide to stay with the 32-bit version of Windows XP, then you won’t be able to access more than 4 GB of RAM. Even if the chipset on your motherboard allows more than 4 GB of memory, your operating system will only be able to use 4 GB of that memory.

If you use 64-bit Windows 7 on a 64-bit system with 24 GB of RAM, then your operating system will be able to utilize all the memory that you install. While this may seem great, how much of that memory can be used by an application is dependent on how that application was developed.

For example, an application such as Photoshop, which is 64-bit, will have a virtual address space of 8 TB, so it can utilize most of the installed RAM for it’s virtual address space, mean it will use the pagefile less.

Games, however, are a different story. Most games are still 32-bit, even if they are installed on a 64-bit system, so the most each game will be able to access is 4 GB of virtual address space (total memory and pagefile). This is important to remember if you plan on installing 16 GB just for a game. The game won’t take advantage of all that RAM because of the virtual address space limitation.

Of course, if you like to load many applications at one time, then having more memory installed will greatly improve the performance of your computer as there will be less need to use the pagefile.

There is no one-size-fits all scenario when it comes to how much RAM you should have installed in your computer. The amount of RAM you will need depends on what you will doing on your computer, the type of computer (32- or 64-bit) and the operating system that is installed.

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14 Responses to “How Much RAM Should Be Installed in Your Windows Computer?”

  1. great article about RAM but sir i have a confusion what is the difference between RAM(Random access memory) and ROM(Read only memory)?

  2. Cathy says:

    Very good read.

    Just a bit unclear on when you say “if you like to load many applications at one time, then having more memory installed will greatly improve the performance”

    Given the limitations of a 32-bit OS, if one is to install 6gb ram lets say, then how will having an extra 2gb ram improve performance if the OS can only access 4gb? Won’t that extra 2gb become redundant/irrelevant?

  3. Umar Rashid says:

    From the beginning of computers era, Ram is the most important topic. Thanks for sharing great information.

  4. shenoyjoseph says:

    i always stick with windows 7 32 bit it uses less ram up to 3GB. if you added more than that there will be no use.

  5. Juan says:

    for me, 4GB Ram is more than enough

  6. Anton Koekemoer says:

    Yes – Even though it refers to physical RAM installed on your motherboard – one can always opt to use DRAM as well. Which can increase the amount of RAM your PC can have installed. Though there are certain benefits when using DRAM it’s not a replacement for Physical RAM – This should only be used as a last resort. Unless you have good Technical knowledge and know exactly why you want to install DRAM.

  7. Carolyn says:

    Hi Paul? I would upgrade the memory of my laptop in a heartbeat, but I’m looking forward to getting a new laptop when Windows 8 is released. Upgrading memory is very easy and cheap, but I’ll tough it out until then.

    This explanation is very useful though, for those who need a speedier machine. I’ve never seen this explained befor, so this is quite useful!

  8. Samual says:

    With resource hungry new applications coming everyday, 4 GB seems to be less for X86.

    • Paul Salmon says:

      It does seem to be less, but unfortunately, it is the limit. With 64-bit systems now the norm for new computers, it will be only a matter of time before all applications are 64-bit and the memory limit is raised to 192 GB for home desktops, and more for future operating systems.

  9. Sarah says:

    It usually depends on the users how they want to use the computer. According to operating system i used, minimum 4GB RAM is necessary.

  10. Aasma says:

    I agreed, that’s why whenever you go to buy any PC… one common question is asked all the time “what’s the purpose of your system purchase”?

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