My PSU is terminally ill?

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allstarnz

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#78293 2-Mar-2011 16:02

I seem to have a dieing PSU. For the past few days after numerous tries, I have finally been able to get my computer to boot. This usually required a bit of jiggling of cords and praying to the computing gods. Once I got my PC started up, it was fine, no issues.

But this morning no more.

When it didn't start up, it wouldn't start at all, or if I was lucky the back fan would slowly start spinning, and nothing more.

Time for a new power supply?

USB devices seem to be fine. My little snake light was powered just fine.

xpd

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#444845 2-Mar-2011 16:21

Sounds like time for a new one... just to make sure, see if you can borrow a PSU tester from someone and see what readings its giving.

Weve got a tester at work and its saved us throwing out a few PSUs :)

XPD / Gavin

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Ragnor

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#444854 2-Mar-2011 16:30

If you are relatively tech savvy you can use the "paper clip trick" to fire up the PSU sans the motherboard and other hardware and use a multi-meter to test the 5v and 12v voltage coming out at the molex plugs.

Eg:
http://www.youtube.com/watch?v=tjs_61NBshw
http://www.youtube.com/watch?v=VXzrCr0RLm4

allstarnz

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#444968 2-Mar-2011 20:39

thanks guys, will do.

funny thing is, I gave up, went to work. When I got home, my pc was on. It booted about 20 mins after I left for work :)

Ragnor

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#445030 3-Mar-2011 00:06

Some PSU's seem to have a circuit breaker type fuse, after a spike or surge it shuts down for awhile and won't turn on for a bit.

Regs

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Snowflake

#445033 3-Mar-2011 00:19

sounds like a failiing capacitor.... but anyway, go buy a new power supply.

i can totally recommend one of these: http://qmb.co.nz/p.aspx?108705 AcBel iPower 510W intelligent 20pin & 24pin Black Retail 12cm Fan Power Supply

quiet with a 12cm fan, well rated on the net, and nearly < $100

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Niel

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#445046 3-Mar-2011 05:52

It is failing capacitors. After warming up a bit the electrolyte is more active and the power suplly is able to hold regulation. You get the same issues with video cards but usually the BIOS would just warn you about a missing video card (beep a number of times when you power-up).

I've fixed a number of power supplies, motherboards and video card by replacing a few capacitors. But only because I'm an electronic engineer and have an interest in it. It is much cheaper to buy a new one, motherboards and power supplies use capacitor values that are not common off-the-shelf items. I have to get them off eBay.

By the way in the mid 1990's there was a problem with capacitors overfilled with electrolyte and failed within a very short time. Affected nearly all PCs, because they all used the same capacitor manufacturer. Had similar symptoms, but was the motherboard.

You can never have enough Volvos!

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Shop now at Mighty Ape (affiliate link).

allstarnz

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#445162 3-Mar-2011 13:48

they'd run out of those, so I rang them, and the guy recommended this instead

Ordered it, can't be bothered hunting round for hours for the perfect PSU

http://qmb.co.nz/p.aspx?107059