GeForce 7800 GTX in Theoretical Tests
We performed a full cycle of theoretical tests to reveal the potential of the new graphics processor from NVIDIA. We made use of the following software:
- Marko Dolenc’s Fillrate Tester
- Xbitmark v0.60
- 3DMark 2001SE build 330
- 3DMark03 build 360
- 3DMark05 build 120
We traditionally begin our tests with Marko Dolenc’s Fillrate Tester.
The diagram shows that the GeForce 7800 GTX isn’t much faster than the GeForce 6800 Ultra at single-texturing. At multi-texturing, however, their graphs diverge more and the advantage of the new solution becomes evident. The GeForce 7800 GTX is by half faster than the GeForce 6800 Ultra when mapping three or four textures. Well, it means it does have 24 pixel pipelines!
Note also that the results of the GeForce 7800 GTX are rather far from the theoretical maximum which is probably due to the relatively low memory clock rate.
It’s generally the same picture with disabled Z writes. The RADEON X850 XT Platinum Edition is much slower than the GeForce 7800 GTX as well as the GeForce 6800 Ultra in both cases.
So, the GeForce 7800 GTX behaves similarly to its predecessor, but is evidently limited by the memory performance.
The GeForce 7800 GTX has 16 ROP units rather than 24, so its fill rate when working only with the Z buffer is almost the same as the fill rate of the GeForce 6800 Ultra. The newer solution is ahead because of a minor advantage in the core frequency (430MHz against 400MHz).
By the way, the GeForce 6800 Ultra and GeForce 7800 GTX both exceed the theoretical maximum in this test. We don’t know yet how to explain this fact.