Radeon 6870 751Mb??

[PowerPie5000]

Why do some utilities such as DX11 and 'Can You Run It' show my total video memory as 751Mb? My XFX Radeon 6870 is supposed to have 1Gb dedicated. Does Windows 7 Aero use around 250Mb video memory when running at 1920x1080? Seems quite a bit just for desktop use.

[kalniel]

Are you on 32bit windows?

[PowerPie5000]

Are you on 32bit windows?

No, i'm using Windows 7 Home Premium 64-bit with the latest AMD Catalyst drivers... Full specs of my rig can be found in the drop down menu below my username.

[kalniel]

Not sure then. Almost certainly irrelevant, but it could be that windows or whatever has reserved a portion of the address space - it'll free it up if it was ever needed though.

[MadduckUK]

hmm. meh

[Yosh]

Just checked my new XFX 6870 Black Edition 1GB and it shows up at 747MB, uh!

Edit: I got a friend to check his card, XFX 6870 Black Edition 1GB and its showing up at 751MB..

Taken from DXDiag 32/64.


What card do you have?

Edit: Found this http://support.microsoft.com/kb/2026022

[MadduckUK]

thats a 5850 512MB at work

It is all a lie.

[PowerPie5000]

Just checked my new XFX 6870 Black Edition 1GB and it shows up at 747MB, uh!

Edit: I got a friend to check his card, XFX 6870 Black Edition 1GB and its showing up at 751MB..

Taken from DXDiag 32/64.


What card do you have?

Edit: Found this http://support.microsoft.com/kb/2026022

I'm also using an XFX Radeon 6870 Black Editon. That link you posted is interesting as it says MS are working to resolve the issue although the article is dated May 2010... Taking their time aren't they?

Here's a quote from the article:

On a system with 1GB of video memory, the following values are returned with the associated system memory:

System Memory Reported Approximate Total Memory
4GB 3496MB
6GB 454MB
8GB 1259MB

Funny as my PC has 8GB RAM and a 1GB GPU... But still only shows 751mb of video memory.



I get the same result when i run 'DxDiag' in 64-bit mode too!

[PowerPie5000]

It seems Windows 7 display properties shows the GPU info more accurately...



I'm guessing these are the correct figures that should have been displayed when running DxDiag.

[jim]

Brilliant.

Does anyone want a 2.8GB 5870?

[PowerPie5000]

Brilliant.

Does anyone want a 2.8GB 5870?

I'm pretty sure any video memory shown above 1GB (or whatever dedicated memory size your GPU is supposed to have) is taken from the PC's main RAM which can vary depending on how much you have installed... It's used as extra texture memory if needed.