I've come up against a problem I've been unable to solve. My computer keeps burning out power supplys. First they smell hot then POP and sparks, smoke...all the neat smells.
  My computer is a home built. I use Windows XP Home. I have a Shuttle AK39 Mother board.  AMD XP 2.2 cpu. 512 DDR333 memory. Santa Cruz sound card ATI 9200 Vid card. 2 40 gig Maxtor hard drives set up master and slave. DVD disc player and Aopen CD burner.
  This computer has worked flawlesy for over 3 years. But in November we had a thunder snow storm and we lost power. The power went out completely then came on with the lights going really bright(surge) and then went out.
  I have a strip power surge protector but it never tripped.  
  Anywho, the computer booted and ran fine for days after the storm, then the 350 watt PSU burned out. It was an expensive one, over 70.00 and it worked well for three years.  I bought a new 400 watt unit off from a vendor online and it worked well for about 3 weeks then pop! So I figured it was a cheapie(30.00). So I went out and bought a 450 watt unit. It worked for less than 4 days.
  Symptoms are, the computer will first crash then reboot automatically, then run fine for a short time then the PSU pops.  Last NIGHT the comp took awhile to reboot and showed a "severe error occured" at the beginning of the desktop load screen. This is the first time this message showed up.
  Now, my system temp stays at 37* C and the CPU is running 39* C. Way below the auto shut down.
  I DONE a BCM hardware test and everything passed with no problems.
  I've checked my house voltage and it's a steady 121 volts peaking at 123.7, same as other buildings on my property.
  I don't see any burned spots on my MB but 3 power supplys in less than a month? Any ideas?
  Would a bad MB cause the PSU to BURNOUT?
  My master HD runs a bit warmer than the slave but I attribute that to it being worked more.
  HELP!
Have you checked for a short in your power cable or your in-house wiring?Yes, the house has been checked by an electrician. I've used the new cords that come with the new power supply. I've also checked for a GROUNDING problem with the computer case.Cheap PSU's are what they are...it's not uncommon to run into 2 or 3 in a row that fail.

Buy a reputable PSU and chalk it up to experience.