PCI Express, Continued
The following tests were run on a Gigabyte GA-8IG1000 Pro (i865G) Motherboard with 1024 MB of RAM and an Intel Pentium 4 processor running at 3.2 GHz. The Bios of this board allows us to set the AGP speed to AGP 4x or 8x. Drivers are Catalyst v4.2 for ATI and Forceware v53.03 for NVIDIA.
The tool VARMemBench allows us to test the available AGP bandwidth. What's surprising: It does not work properly with NVIDIA's newest v55.06 drivers.
In terms of graphic cards, we chose the ATI Radeon 9800XT and NVIDIA GeForce FX 5950 Ultra with 256 MB of memory each and a GeForce FX 5700 Ultra with 128 MB. Lower memory numbers such as 64 MB can only be found on entry-level cards today and those cards can't run the applications we used in good performance anyway.
We used the highest quality setting available in the game. As you can easily see, the bus performance does not show any differences at all.
Next test is the same benchmark with 4x FSAA and 8x Anisotropic filtering enabled. This configuration requires more memory but even the 128 MB FX 5700 Ultra does not show any real differences. Note: We were faced with sustained crashes with the Radeon 9800 XT in 1600x1200. We're unsure if it's a motherboard or driver related issue.