well I got an MSI K8 neo4 Platinum mobo; an AMD 3500+ CPU; an ATI x700Pro vid card; 1gb of corsair xms ram running at 2-2-2-5 1T. The graphics arent up all the way but I punch out an average of 55-57 fps and the game looks sweet.
Also I built this pc over a year ago and the partts were mid to high mid performance wise. I spent around 1300 for it and for that price now you can get a much better system.
If you want some general guidelines for pc parts, get at least a 256mb vid card, a d@mn good mobo like a dfi lan party or asus, along with an opty 165 or a dual core athlon 64 around 2.2 or 2.4ghz. some corsair xmx or ocz ram. That basic set up will put out great resluts on games (I'll ball park the price at 1500 on the cheaper side) but as new stuff from amd and intell are soon to come out who knows what will be better on the top end.
Athlon XP 2000+ OC to 1850 from 1667
2x512 GB PC 4000 (3-3-3-6)
Agp GeForce 6600Gt
It runs great for me, something above 30 fps. Above something like a AMD 3000+ I don't think you'll even see a difference in the frames. I've used fraps in the past its alright, but i'm sure there are better ones.
Compleated the game on (1280X1024 2XAA 8XAF 'settings set to max apart from soft shadows'):
Kingston DDR400 2GB's
Radion X800 XT PE 256MB
Soundblaster Audigy2 ZS Platinum Pro
Cant remember the FPS but I beleave it was about 50fps - 70fps Anything over that should play games fine... The only game that slows down my system even now is Oblivion which still runs at 20fps with everything maxed out so a nice next gen GFX card should bring that up to about 50fps.
I am using the below system and it runs great. I run it at nearly maxed 2xAA and 8x AF and it runs very smooth. I can run totally maxed but in some battles online with a lot of people and grenades in one room it tends to slow to 20fps so I backed it off to the above settings, I average 70-80fps. What ever system you decide to buy or build I would recommend the 7900GT, its tough to beat for the price.