Ok guys I cleaned out my drivers and that did the trick. I'm getting way better frame rate. Now running COD4 with AAx4 max quality at almost 100fps. I checked my voltage and it looked ok but I think Im still going to invest in a new PSU because its about 4 years old (due for upgrade).
I just installed a Visiontek HD 4850 in my computer that has a Antec 350w power supply. On the box it shows on the system requirements that i needed a 450w power supply. I downloaded the COD4 demo, ran it at 1440x900 (aaX4/ aaX2 / aa off)and it ran really choppy even with AA off. I want to know...