I finally messed around with different graphic settings and found that the mouse acceleration and lag seems to be linked to what FPS you get. I dropped everything to low and the aiming and movement was perfect at 100-150 fps. I started bumping the graphics up tho and the mouse acceleration and delay started becoming noticeable even at 60-70 fps. Anything below 50 and it becomes a lot harder to aim for me. At 100 fps I was able to kill enemies at around 400 meters. At 35-45 fps(settings on normal) i had trouble killing enemies that were right in front of me. My specs are 8400 oc to 3.6, 8800 512 gts oc, 4 gigs ram, and XP. I understand that at low fps its gonna be laggy but I don't understand why the mouse seems to have acceleration and delay when your getting 40-50 fps but dosnt have it at all at 100 fps.