some people may not know this.. DOOM 3 has issues with ATi cards. as it was built of off nvidias system, and iD actually recomends nvidia i have a geforce fx 5700 "LE" low end. not the greatest card its half the punch of a normal 5700 and i run it under 1028 x 758 or whatever resolution it is i dont remember. i run it on high not "ultra high" with a 2.8 proccy 512 ram and its only laggy when i get into alot of detail and it has only lagged once.
I am using Digital Surround sound USB speakers

so the sounds friggin make me jump out of my seat last night i was laying in bed for 3 hours afraid of a imp coming at me!
o_O