I'm getting stuttering in high graphics games like Rappelz and Starcraft 2 though. Maybe it's related to my PSU burning out?
Stuttering isn't really indicative of a power problem.
A power problem will usually cause bluescreens, reboots, or the game to crash back to desktop. Stuttering can be caused by insufficient system memory, background processes/programs, insuffient CPU horsepower, or depending on resolution/video settings, an overworked videocard. Sometimes drivers play a part.
First things I look for are intermittent hard drive activity during games when the stuttering occurs. Does the HDD activity LED flash when in a game? Look in task manager and see what is running, and how much CPU time is getting eaten up. I have seen antivirus programs/firewalls cause oddball behavior with online games as well. Just eliminate one problem at a time.
I am a retired Ford tech. Next to Fords, any computer is a piece of cake. (The cake, its not a lie)
3770K @4.5, Corsair H100, GTX780, 16gig Samsung, Obsidian 700 (yes there is a 700)