My vote is for a flaky power supply. Stick with the name brands mentioned previously Antec ,Corsair,Thermaltake. The "rebranded " ones at BB will probably let you down too. Keep the dust bunnies at bay at least twice a year with a good clean out with an air can. If you want to live longer take the machine outside so the significant other doesn't want to clean your clock.

 

I've got an Antec ordered. After some research, I decieded against the BB unit.