GPU problem?

[Headcase]

Hiyo fellas.
So here's what I'm going through right now. I just got my computer hooked back up with my new PSU, which is an Xclio 500 Wt SLI/Crossfire Cert PSU. The rest of my specs are in my signature. The problem is this:

Whenever I boot up up any game, the entire computer locks up.

GTA IV causes both screens to stay black (but powered) and froze completely.
Other games like CSS cause it to freeze after the game has finished booting, and at the menu. I've also noted that the boot screen, where it prompts you to go to BIOS, takes a good while longer on boot up. The computer runs fine when I'm web browsing or doing other trivial things, but games cause it to freeze up. I've googled around, but haven't found anyone having a similar problem. The GPU worked fine before I replaced my PSU (which eventually started smoldering, thus, the new PSU). I doubt, however, that the PSU going bad damaged my GPU. Any ideas? Am I in the right ballpark?

GPU is a VisionTech ATI Radeon 4850 512 Mb 256bit.

 

[Headcase]

Update: Upon booting up L4D, It worked, however every few seconds the computer flashes black, as if it's going to lock up. The monitor in which the game is on has faint thin gray vertical lines, before it quickly changes back, to repeat the process in a few moments. The vertical gray lines appear quickly on a boot up of CSS, but then go away to lock the computer up. I tried V Sync and no V Sync, both causing the same result. I'm thinking artifacts?

 

[Headcase]

Update: After reading, I think it may be a VPU recovery error. I'm going to try disabling VPU recovery, and seeing if that works. I'd really appreciate some extra input on this.

 

[Headcase]

Problem solved.