Can I use a 4GB Video Card in Windows XP 32bit with 4GB System RAM

[saber2600K]

Dear Reader or Responder,

First I want to thank you for your time spent reading/responding to this message.

Here is the situation. I am a very experienced computer user.

I run both Windows 7 Pro 64bit and Windows XP Service Pack 3 32 bit edition (they are on different hot swap drives). I only use Windows XP to run software and games that will not work in Windows 7 64bit. Otherwise Windows XP is not my primary operating system.

The problem deals with memory and the address space XP handles in 32bit. I have always been informed about the memory limitations of a 32bit OS. I currently run 8 GB of memory (RAM) on my motherboard. I am aware that 4GB is the maximum the OS can see and use.

I have decided to replace my EVGA 580 1.5GB video card with a brand new EVGA 770 4GB video card. According to the website for EVGA, Asus, and several other 3rd party board makers and Nvidia (who provides a driver for XP) the 4GB video card will work in Windows 32 bit and 64bit version of the OS. I currently run the Windows XP Home Edition version.

Now I have always known that there is a limitation of XP in how much memory can be addressed. That amount is the approx 4GB of RAM minus the Graphics Card memory. So with a 1.5GB video card, that means you won't be able to have more than ~2.5 GB of memory available to the operating system (before other drivers and software loaded at the start of the OS and then of course programs you run).

I am an experienced user and so this has me baffled and I can not find any tech/support/briefs on the issues of how a 4GB video card can be used in a 32 bit edition OS that can only access 4GB of memory no matter how much memory (RAM) is in the system. With all the companies saying their 4GB card can be used in Windows XP 32bit, I don't see how, since 4GB - 4GB = 0GB, that would mean Windows XP should not be able to run as their is no space left for addressable memory.

Can anyone confirm how a 4GB video card will work in Windows XP Service Pack 3 32bit with 8GB of RAM? Is there some sort of hardware/software/driver/switch/command that disables a portion of the video card memory so Windows XP can run? How or does a 4GB card actually run in Windows XP and more importantly can Windows XP run? I really can use your expert advice and help in resolving this issue.

Just a reminder, XP is on its own hard drive (I used a Hard Drive Swappable Bay, that allows me to run XP and 7 on seperate drives. Xp is only used to run software and yes, no lying, games that will not operate properly in the Windows 7 64bit Pro edition and will not work or needs things that the Windows XP mode for Windows 7 can't provide.

Please help as I have a nice brand new EVGA 4GB 770 FTW video card I bought at an unbeatable price and would love to keep it.

Thanks you once again for your time in reading/responding to this message.

 

[Janus67]

I would bet that it can work at least from seeing benchmark submissions from cards using xp as the OS that have that much memory. But would have to double check to be sure.

http://m.hwbot.org/submission/2392824_sofos1990_3dmark2001_se_geforce_gtx_titan_187356_marks

Is a link to a 3dmark01 submission on xp32 with a titan (6gb vram)

 

[kyfire]

On a discrete video card the memory is not added nor subtracted from system memory. It's video memory. In the case of on board video (built into the mother board yes part of system ram is used for video. this is not the case when you have a discrete video card.
So yes you card have a video card with 4GB and it will work find with Win XP 32bit.

 

[saber2600K]

Yes, while Video memory is different from your Main System RAM, many tech articles regarding Windows always says that when determining how much memory is available that you have to take system ram minus video card ram (due to memory address having to be reserved for the video card, will result in a reduction of available memory address space).

I know that the best/easiest solution is put the card in and see what happens. It is just that the card's memory based on all my knowledge and experience with windows, should technially not work, which is why I wondered if the drivers or hardware has found a way to either limit how much memory the card initially uses or how Windows reserves mapped address in the memory for the 32bit OS.

Since pretty much all 3rd party vendors say Windows XP 32bit/64bit is supported, I wanted to understand how it does truly work despite the limitation of the 32bit OS in regards to memory address being addressed.

Here is a clip from another site that I have seen in PC Gamer, PC World, PC Magazine, Maximum PC, etc. regarding this issue:
"The limitation isn't on memory at all, it's on the address space. Things like video card memory need to be addressable, as do many other peripherals (though their usage of address space is generally small). Unfortunately for 32-bit systems, your video card memory falls into this category, if it were addressed separately DMA wouldn't work and there'd be no fast way to transfer texture/polygon/shader/etc. data to it.

If you have 2x1GB of video memory, that address space will not be usable for system RAM (under Windows) in a 32-bit system."

 

[magellan]

Yes, while Video memory is different from your Main System RAM, many tech articles regarding Windows always says that when determining how much memory is available that you have to take system ram minus video card ram (due to memory address having to be reserved for the video card, will result in a reduction of available memory address space).

I know that the best/easiest solution is put the card in and see what happens. It is just that the card's memory based on all my knowledge and experience with windows, should technially not work, which is why I wondered if the drivers or hardware has found a way to either limit how much memory the card initially uses or how Windows reserves mapped address in the memory for the 32bit OS.

Since pretty much all 3rd party vendors say Windows XP 32bit/64bit is supported, I wanted to understand how it does truly work despite the limitation of the 32bit OS in regards to memory address being addressed.

Here is a clip from another site that I have seen in PC Gamer, PC World, PC Magazine, Maximum PC, etc. regarding this issue:
"The limitation isn't on memory at all, it's on the address space. Things like video card memory need to be addressable, as do many other peripherals (though their usage of address space is generally small). Unfortunately for 32-bit systems, your video card memory falls into this category, if it were addressed separately DMA wouldn't work and there'd be no fast way to transfer texture/polygon/shader/etc. data to it.

If you have 2x1GB of video memory, that address space will not be usable for system RAM (under Windows) in a 32-bit system."

I have a 2GiB Diamond 6970 that has been working fine in Windows XP Pro 32-bit with both 4GiB of system RAM as well as with 8GiB of system RAM. The same amount of memory is reported as available to Windows XP Pro 32-bit with either 4 GiB of system RAM or 8 GiB of system RAM (with the Diamond 6970 installed). It could be that Intel's PAE, which extends the address space to 36-bits, may be at work here.

 

[kyfire]

The following is from HP Understanding how Video Memory is used (Windows 7).....
Dedicated Video Memory: Memory set aside for the exclusive use of the graphics adapter.
For Integrated Graphics Cards, this memory is set aside by the BIOS and is subtracted from system memory before Windows 7 is loaded. Windows 7 does not report this as part of total system memory.
For Discrete Graphics Cards, this is the memory that is on the graphics card. It is not subtracted from system memory.

Here's the link ( contains a very good explanation of video memory) http://h10025.www1.hp.com/ewfrf/wc/document?docname=c02001494&cc=us&dlc=en&lc=en