Power Problems

dgre005

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Jun 1, 2008
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I wasn't familiar with the old motherboard power system...so when I was connecting the ATX connector (20+4 pin)I inserted the 4-pin part into the 12V sockets by mistake. I switched on the PC, and surprise surprise it didn't power up. Now that I have all the correct power connectors in place, the PC does power up(an Asrock nForce3 250 Socket 754), however the BIOS only recognises the CPU and RAM and then restarts. Pressing F2 I can't get into the BIOS either...I'm starting to think I've ruined the mobo.

Could it be anything else?

Thanks.
 
You might have a defective motherboard, but I doubt if your mistake damaged the motherboard. The 4 pin EPS connector has two 12 volt lines and 2 ground lines. The "4" part of the main plug has one each ground, 3.3, 5, and 12 volt lines. So if you plug that into the EPS plug, one of those lines will be shorted to ground which will electronically shut the PSU down.

You will not be able to enter the BIOS until you complete the POST.

Look at a this for troubleshooting ideas:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems