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Is my PSU dead?

Last response: in Components
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February 28, 2011 4:10:51 PM

Hey,
today my PC froze completely when I was browsing the web, I rebooted and got a beep code telling me I had a power error. So I tried disconnecting everything, except for the essentials, but I got the same error.
So I thought I'd test my PSU using a multimeter, I shorted pin 15 and 16 to turn it on and the fan only spins briefly. I measured all pins on the 24 pin tx connector, and I got these results:


pin normal measured
1 +3.3V -3.73V
2 +3.3V 0V
3 gnd 0V
4 +5V 0V
5 gnd 0V
6 +5V -3.73V
7 gnd -3.73V
8 pwron -3.73V
9 +5VSB 0V
10 +12V1 -3.73V
11 +12V1 -3.73V
12 +3.3V -3.73V
13 +3.3V -3.73V
14 -12V 1.3V
15 gnd 0V
16 ps_on 0V
17 gnd -3.61V
18 gnd -3.73V
19 gnd 0V
20 -5VDC(optional)-3.73V
21 +5V 0V
22 +5V 3.73V
23 +5V 3.73V
24 gnd -3.73V

The results looks very, very strange to me. My powersupply is a 3 year old Corsair TX650W.
Is it fried? Am I measuring this the wrong way? All was done using the DC setting on the multimeter.
Any help appreciated :) 

More about : psu dead

a c 710 ) Power supply
February 28, 2011 9:07:24 PM

Those readings do not make sense unless it is broken! Measure all the voltages to ground (black wire), they are color coded +5 volt red +12 volt yellow 3.3 volts orange http://www.playtool.com/pages/psuconnectors/connectors.... you should only need one reading of each voltage because they are all single rails.
a b ) Power supply
February 28, 2011 11:57:12 PM

Looking at the voltage readings it looks like to me that you connected the negative lead of the multimeter to the +5v to avoid confusion you should connect the negative lead of the multimeter to the centre leads of the 4 pin connector.
Even then the voltages are still very wrong. I would suggest that you substitute the power supply with a known good one as it fails the paper clip test it is almost certainly faulty

Related resources
a c 285 ) Power supply
March 1, 2011 12:01:57 AM

Check the battery in your multimeter to make sure its good, if the battery is dying it can give some interesting results, someone at jonnyguru had that issue.


Also, as other have said, make sure you are measuring with the negative lead always in the black connector wire since its impossible for you to get a negative voltage off the positive rails, and you really shouldnt have had a voltage on any of the grounds, if you do thats either test equipment or measuring issues since by design its impossible.
a b ) Power supply
March 1, 2011 12:10:43 AM

Sure fire test put another psu in.
March 1, 2011 12:39:17 PM

I did connect the negative lead to gnd ;)  Anyways, I tried doing the test again, and I got the correct voltages... For about 5 minutes. Anyways, when I shorted pin 15 and 16 the PSU made this strange clicking noise(sounded like a short), so I'm starting to think it's the PSU that's broke.
!