Power Surge damage

benikens

Distinguished
Jun 8, 2011
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We had a power surge the other night, since then my roommates computer been experiencing strange issues. Firstly it likes to sit for a long time at POST before moving on, like sometimes its there for 20mins. Also his alt ctr and shift buttons all stopped responding regardless of the keyboard he was using. Then he started to have crashes etc while playing games. What's most likely to have been damaged? I assume motherboard or possible the hdd because of the boot issues and windows problems but I'm not entirely sure. The power supply doesn't seem to be damaged, I haven't smelled any smoke or noticed anything suspicious.
 

andy_in_kenya

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Dec 11, 2011
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Hi,

try another power supply. It's the first thing to take the blast if you get a power surge. Could well be a blown or half-blown capacitor on primary or secondary side.
I'd recommend to borrow a known good psu from a friend and try the machine with that one. Run it for some time to estimate whether it is stable or not.
Also - while you swap the psu - take the CMOS battery out and set the CLEAR CMOS jumper to clear. I've seen BIOS settings messed up by power issues. Only put the jumer back to normal position and the battery back *BEFORE* you plug the new psu into mains.

So the steps would be

- disconnect old psu from mains
- take battery out
- set jumper to clear position (mostly pins 2-3)
- disconnect old psu from motherboard
- lean back, take a break, WAIT FOR 5 MINUTES
- connect new psu to motherboard
- set jumper to normal position (pins 1-2)
- re-insert battery
- connect psu to mains
- fire up machine
check whether it is running welll and stable...

Hope this helps...
Best
Andy
 
Yep, I was just going to say that. Reset the BIOS first, then start troubleshooting what needs to be replaced. Most likely candidates for replacement are the power supply, motherboard, and HDD. CPUs, GPUs, and Ram tend to survive, but you never know until you can properly test them... and testing them can fry things too, so be careful.