X-bit labs

NVIDIA GeForce 6800 Ultra and GeForce 6800: NV40 Enters the Scene (page 20)

Category: Video

by Tim Tscheblockov , Alexey Stepin , Anton Shilov

[ 04/14/2004 | 01:48 AM ]

Synthetic Tests: Vertex Processors

There’s no need to comment: the NV40 is unrivalled and its high fill rate and fast memory subsystem allow it to have a smaller performance hit in higher resolutions than its competitors have.

The GeForce 6800 Ultra is the fastest, too, at executing version 2.0 vertex shaders.

Synthetic Tests: T&L

In fact, all benchmarks of the execution speed can be now regarded as measuring the vertex shader execution speed, since all modern graphics processors translate commands of the classic T&L into appropriate vertex shaders. We’ve got curious results:

The GeForce 6800 Ultra is faster than the other cards at processing a one-light-source scene, but the gap is smaller than in the pixel shader tests.

The GeForce 6800 Ultra remains the leader in the test with eight light sources, but there’s even smaller difference between the results of the NV40 and the NV38. That is, having six vertex processors and, potentially, twice higher geometrical performance than the NV38, the new NV40 core is only a little faster! This signals about a less efficient translation of T&L instructions into shaders in the NV40. This problem may be amended in the future version of the driver as the NV40 shows very satisfying results in all other geometry tests.