Question about Graphics Memory

Gate9er

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Hi

Why do I have 896MB of ''Dedicated graphics memory'', when I have a ''Total available graphics memory'' of 4095MB?? The rest 3199MB goes to ''Shared system memory''. Can I change that, so that I can get max graphics memory as I play a lot of games?

P.S. I have a GTX260 in SLI config.

Regards
 

Vettedude

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The shared memory is a ton slower. You can't upgrade the Dedicated memory as it is soldered onto the graphics card. And amount of memory doesn't matter as much as the speed (GDDR5 vs GDDR3 and the bus size)
 
Short answer: No.

Longer answer: No, because ...

1. Your graphics memory is 896 MHz even with SLI'd video cards.

2. nVidia cards cannot use system memory to augment the frame buffers on the video cards. And even if they could, it would be a lot slower.

 

Vettedude

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SLI does NOT just add the memories together. Instead it writes the same stuff to each cards memory to keep them synced together
 
A GTX 260 has 896 MB of graphics memory, in SLI or CF the memory does not add as each card stores the same stuff on its memory so even though you have 2 GTX 260s in SLI with each having 896 MB of graphics memory, the combination still only has an effective 896 MB of graphics memory, and you cannot do anything to increase that.

The shared system memory is just because the card is able to store some stuff on the system ram, but cannot use it as a frame buffer like it uses its dedicated memory. Once you bought a card there is no way to increase its graphics memory.
 
Yes, you have twice the compute power, but you don't have any more memory so for memory intensive tasks like AA and extremely high resolutions you will still run into a graphics limit at the same point if those are what were limiting you.