I'm running a q6600 at stock speeds (2.4ghz) with an ati 5850 (just replaced an 8800gtx) and 4gb ram on win7 64. I'm trying to run these games 1920x1200

I noticed that in a handful of games like Oblivion, Alien Swarm (steam), and Booster Trooper (steam) are stuttering every few seconds even though fraps says i'm getting a stable 60fps with vsync on.

then other games like bioshock 2, counter strike source, and starcraft II don't have any issues.

I tried OC'ing to 3.0ghz with the same results. I'm not sure if it's a cpu bottleneck and I should upgrade to a newer processor. I didn't see any kind of cpu spiking though that might be causing the problem.

Anybody have any tips for troubleshooting what could be the cause? I have tried different resolutions on some of the games and it helped but oblivion I get skipping no matter what, even running at 800x600 getting over 150fps while inside a building.

I just don't understand why FRAPS is saying a steady 60fps in these games and yet they are still stuttering.