GeForce2 Ultra Review (10/12)

Overclocking

Good cooling guaranteed

If you thought 460MHz was fast for memory, try 500MHz! That's how high I could get my sample. Strangely, starting with 501MHz, I would get gibberish on my screen and the system would lock up on me. Looks like the clockgenerator can't handle higher speeds - too bad *sigh*. The chip would work reliably at speeds as high as 295MHz. Well, it could go beyond that, but strangely the performance would then drop. So I decided to run all tests at a 295/500MHz setting - seriously, increased corespeed has practically ceased to be the decisive factor with games for this class of card.

AntiAliasing

When antialiasing is used, memory performance and throughput are of paramount importance. Take for example 2xFSAA. The scene is re-rendered at twice its original resolution by the T&L unit. 2D Overlays like cockpits or text are then scaled in an extra cycle and added to the buffered scene. Then a matrix is projected over this scene (for example with a mesh size of 2x2 pixels) and the average color value of all elements within this mesh is determined. Now the picture is scaled down to its original size and the pixels are given the new averaged color. Additionally, filtering and some other operations are performed.

This causes up to 2-4 times the amount of memory traffic that a normal non-antialiased scene would need, explaining the performance drop incurred when using antialiasing at high resolutions at 32bit color. Each one of these is memory-bandwidth intensive on their own, but put them together, and they become any card's worst nightmare.

Now for a mix of benchmarks consisting of Evolva (Direct 3D) and Quake 3A (OpenGL) with and without antialiasing enabled. For comparison I have included the results of the Hercules 3D Prophet II GTS 64 (220/366).

AntiAliasing Evolva: 2X2 AA (Direct 3D)

The Ultra benefits from it high memoryclock. Remember the amount of calcualation that is needed for antialiasing. So 10FPS faster im the high 32Bit resolution is really impressive.

AntiAliasing Quake3: 2X2 [LOD] (OpenGL)

Almost the same results in Quake3.

Copyright: 06.09.2000 -   RIVA Station 2000 - Lars Weinand
No Copy without Permission!

Translation by Benjamin Kraft

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