need help to fix a lot of psu's.

[ezcharlie]

i have about 5 atx psu experiencing the same problem and i was hoping to try to fix them if possible.
250watts and 300watts..
the problem is when they were working, the pc would suddenly black out and that was it. the power light would still work when i switch on the pc but nothing moves. all fans connected to the psu would just twitch a bit when i turn on the switch. none of the psu's work now. any electronics wiz out there who can help???

[Sophisticated]

best bet is to just buy another PSU

[Tismedt]

Originally posted by Sophisticated
best bet is to just buy another PSU

Well that would be the easy fix for sure, but he is talking about 5 psu's. Lets look at this a bit closer. Is this happening on one rig ie: the same mobo, case, hdd etc?
Will the psu's start outside of the case by using a jumper on the atx plug?

http://www.ocforums.com/showthread.php?s=&threadid=278701

If so you have a short somewhere that is drawing too much juice and tripping the overvolt protection.

[Mico]

Also, what brand and serial number do these PSU's have. (fears for some deers) *shudder* Some PSU's...well, they just don't work very well at all.

[ezcharlie]

all psu's come from diff. pc's. all systems are amd. a k6/2 500 sys. duron 750 o/c 1000 sys's. and xp1500+ sys's. overvolt protection? what's that? maybe thats it but even with the jumper short, the same thing happens. a little twitch from the psu fan then dead. if you reset it, the fan doesn't twitch. you have to disconnect the power then reconnect it so the twitch can occur when trying to switch on the psu.

[Mico]

That sounds really odd...where the systems rather power heavy? (Lots of HDD's, or something), or did you recently add anything to them that may have done this to it?

[Tismedt]

Have you tried to jumper start these outside of the case. I mean sitting on a desk etc? If not do that. Hook up a couple fans to add some load and try it. A psu should not run without some kind of load. A couple fans only works the 12v rail but its better then nothin.

Overvolt protection is just that. If the system draws too much juice from either rail it will shut down the psu. A short in your system can cause that.

[ezcharlie]

i did try running the psu's oiutside the case via jumpers, but no luck whatsoever... if something is shorted inside the psu, what do you think it is and would it cost too much to have it fixed or to fix it myself...

[Mr.Radar]

What brand are the PSUs? If they're a brand like Allied, PowMax or Deer, they aren't worth saving. But if they're a good brand, then you might want to open them up and take a look inside to see if anything blew up or shorted.

[fhanderson]

Have you checked the fuses inside the powersupply?

[isisfreak]

How old are they? Everything dies at some point, you should just get some new PSUs. Even if you do find out what is wrong with each PSU, its not going to be worth fixing.