Burned Power Supply help

[lindberg]

The fan in my ps stopped so after a few hot minutes the ps gave up, I've replaced the powertransistors (they were burned) and now I atleast get current to the mainboard (there is a led on the mobo which turns on). But the prob: When I push the pwr-button it wont fire up (I've tried to shortcircuit the pwr pin on the mobo) so where can the problem be?
Anyone that have a clue or a link to a good site where they deal with powersupply repair/problem?

Thanx in advance

[ayoub_ibrahim]

hmm, wouldn't it be simplier to just get a new psu??

[lindberg]

Yep

Indeed it would, but more expensive

[Greebe]

There isn't... you will have to rely on your own skillz... of course a schematic would be nice, draw one up

[Jammrock]

As Greebe can attest to, my electronics skillz have greatly diminished, but you may want to check and see if you popped a few capacitors or blew a diode bridge. Nothing like a good DMM and some circuit level testing to waste some time

And before you plug it back into the board you should test you voltage outputs. Put an old hard drive on one of the molexes, if you have one, ot use one of your regular ones if you don't. Then take a paper clip or some wire and put it between pin 14 (usually the green wire, if it's an ATX p/s) and ground (any black wire). This will fire up the p/s, the HDD is there to give it a decent load so it will function right. Take you DMM and test the voltages of your connectors. The link has a diagram of the voltage for a standard ATX connector.

http://overclocking.telefragged.com/articles/psutricks-1.html

If all your voltages check out, give it a whirl.

Jammrock

[lindberg]

Won't fire up

The power trasistors after the diode bridge were burned ,so they I've changed.
But now the PS won't start, the only pin where there's life is the +5V standby pin. The PS does not act when I try to ground the standby pin. So it seems like I'm in real big trouble

[Jammrock]

Looks like it's time to buy a new one. You can get a generic 300 W for ~$30 USD.

Jammrock