Instructables

ive had a few PSUs that dont stay on, can i fix them?

ive had a fair number of Antec 350W psus that will attempt to turn on, but dont. its almost as if they dont have the capacity to do it or something.
ive been wondering, since its not capacitors (there are 2 small ones that are usually failed, replacing them does not fix it) could it be the mosfets?

im wondering because ive had a lot of these (at least 10) from computers and all but one had the same symptoms, the one that didnt had a chip blow up on it. but it seems like a waste to take just the fans, connectors and switch if it has one and dispose of the rest, i want to be able to reuse as much of the PSU as possible, even the main transformer and the two smaller transformers if possible.

any ideas on what i can reuse (literally anything i can reuse) or how i can fix them?

orksecurity3 years ago
Can they be fixed? Possibly.Could it be the MOSFETs? Sure, but it could be just about anything until and unless someone goes in with measurement tools and an understanding of how the circuit is supposed to work and actually figures out why it isn't doing so. Which is what should be done rather than replacing parts at random and hoping.

Sanity check: Are you sure the problem is the power supply, rather than in what the power supply is powering? Most PC power supplies try to shut themselves down if there's a short circuit, or if the motherboard doesn't respond appropriately to say it likes the power it's getting. Alternatively, it's possible that when whatever they're connected to malfunctioned, that's what killed the power supply.

Can _you_ fix them? I'm guessing not until you have a better understanding of how they actually work and why they aren't working; see first paragraph above.

There's a reason the pros just replace the whole power supply. Yeah, it costs a chunk of change, but when you compare it to the value of the time and effort it takes to actually fix them the cost of a new one isn't all that unreasonable.
zack247 (author)  orksecurity3 years ago
its definitely the power supply, they cant even keep just themselves powered on.

alright, well other than the heatsinks, plugs and fans is there anything i can reuse from the power supplies?
You have installed the necessary jumper for running them without a PC attached, right?
zack247 (author)  orksecurity3 years ago
jump the green and black wire, right?