Does 512MB Make a Difference?
The highly popular 3D shooter Doom 3 was the first game to declare that it needed 512 megabytes of graphics memory. The developer recommended using a graphics card with that much of memory to enable the Ultra High Quality mode. We did not, however, see any difference in performance between the High Quality and Ultra High Quality modes even in the resolution of 1600x1200 pixels with enabled 4x full-screen antialiasing (for details see our article called Doom III: Performance and Image Quality in Different Gaming Modes).
We also couldn’t see a performance breakthrough when we were benchmarking the first top-end graphics card with 512MB of memory, the ATI Radeon X800 XL 512MB, although it did perform better in a few tests like the legendary shooter Half-Life 2 in high resolutions with enabled 6x FSAA. It was clear that 512 megabytes of graphics memory was not in fact necessary and could only be of some use in high resolutions together with full-screen antialiasing. But in such modes the memory bandwidth and the performance of the GPU would became the crucial factors, limiting the card’s performance.
Our investigation was published back in the spring of 2005 and has become out-dated by now. Not one but several generations of graphics processors have changed since then. There have appeared new games with complex special effects that use Shader Model 3.0 and HDR whereas full-screen antialiasing has long become a customary image-enhancing option for most gamers who enable it wherever possible.
All these visual luxuries do not come cheap, for sure, but do they really require 512 megabytes of graphics memory? Answering this question, we should keep it in mind that many modern gaming projects are multi-platform ones or are planned to be such. And when you come to think of it, even the last generation of consoles like Microsoft’s Xbox 260 and Sony’s PlayStation 3 do not have as much memory as today’s gaming PCs. Game developers make allowances for that, reducing the resolution of textures. To make the game good-looking, they focus on special effects that are based on sophisticated math1ematical computations performed by the graphics processor. The GPU load is very high at that, but not much of graphics memory is employed since there are no huge textures. This trend is getting stronger nowadays and owners of graphics cards with 256MB of memory should not hurry as yet to upgrade to 512MB solutions.
Anyway, we want to see how things stand right now, and we are going to check out the influence of the amount of graphics memory on performance in today’s games. To carry out this investigation we’ll take two versions of the GeForce 7950 GT that suit our purpose perfectly. They are a Gigabyte GV-NX795T512H-RH with 512MB of memory and a Foxconn FV-N79GM2D2-HPOC with 256MB of memory. The Nvidia GeForce 7950 GT is an affordable and rather fast graphics card, so our investigation will have more practical worth. Let’s have a closer look at the two graphics cards now.