I have a 1ghz P3 (oced to 1.1ghz) with 512mb ram, an ATI Radeon 9550 w/ 256mb ram.
I have problems starting the game and occassionally playing it.
75% of the time when I start the game, I see the white logo, and then it goes full screen, but the screen stays black, then about 10 seconds later i crash to desktop and live is now a 640x480 black screen in the upper left hand corner, and its giving me the error report thing. Sometimes it works, sometimes it doesnt.
The same sometimes happens when starting a 5v5 game.
It happens with the normal exe, so I decided to use an "alternate" exe, and had the same problem as well.