Power strip causing instability?!!

[haste]

Ok, so...my 2nd rig has an air cooled opty 165 o/ced to 2.85ghz on an a8n32-sli with some ddr500 memory. i basically use this rig as an HTPC and for all my IM proggies and folding@home, and when my main rig is down I use it for gaming and also lend it out at LAN parties for people to use. anyway, a few weeks ago I was having issues with being able to run F@H, the computer would randomly reboot and/or shutdown after attempting to run F@H for more than a couple minutes. the computer was basically stable with everything else i do on it.
i wasn't in a rush to fix it as its not my main rig, i figured the memory might be going bad or the PSU might be going down the tubes. heat had been a slight issue so i decided to clean out all the dust. it helped lower temps by 4c on my cpu but it still didnt help stability...ran memtest for 8 hours straight, no errors...WTF!!!!!
I have no idea why I decided to do this...but I unplugged the rig from the powerstrip I had it plugged into and plugged it directly into the wall. Perfectly stable since then...no issues. The only other thing I had plugged into the powerstrip was my lcd monitor.

Cliffs:
computer not stable all of a sudden at 100% load
ran diagnostics, everything checked out
unplugged computer from powerstrip and plugged directly into wall. perfectly stable for 5 days now...

i wasn't aware a powerstrip could go bad like that?
anyone else had this problem?