My Amd Athlon 900 Mhz, 384 Sdram, Ati radeon 9700 pro. My fps fluctuate between 25-40, on cell games. You'll notice a drop in FPS if you have a low end system on some of the newer maps, since they make use of a lot of env_models and high texturing(if you choose to use it) My Video card is great but it's bottlenecked like crazy. This is just a guess but.
Minimum:
1-5 Multiplayer, 700+ Mhz Processor, 256+ Sdram, Geforce 2/Radeon Card with (32)64 Mb Ram. 800/600 Resolution(640/480 with more players), High textures off.
Recommended:
1-12 Players, Multiplayer. 1000+ Mhz Processor, 256+ DDR ram, Geforce/Radeon Card with (64)128 Mb Ram. 1024/768 Resolution. (High Texturing may drop 10 +/- FPS)