Performance in Simulators
Colin McRae Rally 2005
The well-known race simulator called Colin McRae Rally 2005 uses a tremendous amount of relatively simple (for today) pixel shaders to create various effects, such as smoke, dust coming from under the tires, highlights, etc. The performance in this game depends a lot on the number of pixel processors and their computational power.
In this case there is parity between RADEON X1800 XT and GeForce 7800 GTX: the first one reaches these heights due to high GPU clock and memory frequencies, while the second one owes its high great results to 24 pixel processors. The high working frequency of the RADEON X1800 XL, however, fails to make up for the fewer pixel processors: 500MHz is definitely not enough to successfully oppose the 20 pixel processors of the GeForce 7800 GT working at 400MHz (at least with the memory working at the same speed). Moreover, here the XL solution yields even to the RADEON X850 XT Platinum Edition, which may indicate that the drivers could use some extra work.
Once we switch to the test mode with enabled FSAA and anisotropic filtering, the situation changes radically. RADEON X1800 XT gets far ahead of everyone else due to its memory working at 750 (1500) MHz and communicating with the GPU via a highly efficient controller. RADEON X1800 XL also outperforms GeForce 7800 GT, and in 1280x1024 even catches up with GeForce 7800 GTX.