Wow. Well, first off stuttering can be a result of so many things. But i'll tell you what just got rid of my stuttering with a few games. I reinstalled my A2ZS drivers again, and reloaded DX9. Two games I had stuttering on are totally fine now. Could also be video drivers need reinstalling again. It can (has been in the past for me) also ram timings too tight with an overclock I had. It passed memtest 86 but after I relaxed timings to about 7-4-4 all was fine (I was running at 235 FSB though). Sometimes it can be a video driver that also needs reinstalling, or parts of an older driver form a different manufacterer (like nVIDA) that have not been totally removed from the registry. Also can be unstable (or uneven power) from your power supply. Specifically when you overclock and the +12v is not rated above about 15A. Usually, my rule of thumb is to start witht he drivers, and work backwards taking into account anything I have recently done to the computer. I reinstall sound, video, and chipset drivers 9as well as DX), and I make sure i'm at stock clocks. it's a good place to start. Then I check voltages on the power supply, and run memtes86 on the memory with the timings I have running at the time. If all else fails you could try more conservative timings (loose timings) on your memory, up to and including "reseating" the modules themselves as well. Sometimes a nice CMOS clearing is needed - but usually only after a hard overclock when things seem to want to not settle correctly. All of this is basically "working backwards". But if it's "jittery" just playing flash, then the very first thing is to consider 'how long" has it been this way? Did you make any changes at all? (like in your bios). Hope this info helps give you some tools to narrow it down. It's always worked quickly for me.