I have fiddled with the config.ini (anybody upload theirs for download?) and disabled community overlay. I'm running as administrator and tried ticking the other options such as forcing it into 640 res. I've applied the newest official and unofficial patch. Someone said something about copying steam.dll into the Arx folder, that didn't do anything either.
2x ATI 5870 (not running crossfire)
i7 @ stock, 3.2 Ghz
12 gigabytes of ram
2560x1440 native resolution
Any suggestions?