I'm getting the following for demo1 and demo2 (max settings, 1280 x 1024 resolution):
1. Asrock 775i65G, C2D E7500 2.93 GHz, (1Gb+1Gb) DDR800 RAM, ATI Radeon X800 XT PE. Demo1: 577 fps, Demo2: 575 fps
2. Asus P5KPL-AM/PS, C2D E8500 3.16 GHz, 2 Gb DDR2800 RAM, ATI Radeon X850 XT PE. Demo1: 500 fps, Demo2: 512 fps
This is really confusing because the 2nd build (on paper) is better than 1st build, yet the 1st build has higher fps. For all other games that I've seen, the 2nd build performs better. Q3A is the only exception for some unknown reason.