Hello all, thanks for takeing some time to look at my thread. Also thanks for your reponses on the matter!

I encountered a users PC today, i walked in on its second problematic boot. The PC was flashing on/off on the monitor. It appeared the monitor was displaying the windows booting image as it should, but it would go "off' and then back "on" at random. When it finally got to the windows desktop, it shutdown. I restarted it a second time and it flashed. It shutdown at the desktop. However, on the third reboot it booted to the desktop just fine. The user needed a reformat also, so i got it to boot to the windows install screen from the windows recovery CD. It managed to load all the files from the cd fine and sat at this screen with no issue. I had a few odd looking errors trying to get it to read from cd, but at the time i can not recall them. However, i got to this screen and sat there. Before counting i decided i should check for a PSU/video error. i opened the CASE and took a peek AROUND, but besides an dust that i sprayed out it looked fine. I SAW dust in the PSU sides so i sprayed that a bit to. (But not enough, as i'll get to.) So then i took the ram out and decided to let it sit for about ten minutes in case anything might have decided to hide in them. I put them back in, made sure they were in step and powered the pc back on. The pc seemed to come on, but i got no display. I turned it back off, the PC made a odd noise and no longer wished to boot. So i opened it once more, disconnected the power switch "ON" wire to the little group on the Mobo, stuck my screwdiver between the two power on input prongs (I'am sure there's a correct technical term, but i've ALWAYS called them prongs.) No boot. I reconnected the switch, no boot.

At this point i wanted to test the power SUPPLY but i discovered two things:

1. We did not have a multimeter/voltmeter on hand, and 2. We had only AT PSU in storage (Why i'll never know.) So i took the case apart, plugged the PSU into the wall, plugged the molex onto the motherboard and connected two different known good cd-roms on the device molexes. Fan on the PSU did not start, nethier did the cd-drives want to open. I stuck on a hard drive, put my ear to it with no spin. I took a lot at the PSU and then noticed a lot of dust still in the cracks, so i opened it and basically a square of dust collapsed and filled the air. So, maybe the dust was the issue, overheated or grounded? I got some of the AT power supplies and tested them (I did these tests with the same power cord as had been used to power the pc when it was booting - i could not find a spare cord.) the cd-roms did not want to open on them ethier but then worked fine when put back into the known working PC. Guess those must be dead as well. I rebuilt the machine, still no boot.


Would anyone else come to the same conclusion of a dead PSU? I plan on testing it with a different cable and a multimeter as well. Any other suggestions as to possible issues would be great Thanks!

edit: Just got a meter, volts go in they dont go out. Fiqures. A quick swap with a known working PSU of sufficient wattage would confirm, but it sounds like a new one would be the next place to go.The only problem with meter testing a PSU is it is not under load...

This is why i don't trust PSU testers either.