petriedish

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Mar 26, 2004
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I'm building a machine and am having a power problem and need to figure out what's wrong. First, I don't get anything at all, no beep code, no case fans, nothing. I unplugged the power supply from the MB and jumped between pins 14 and 15 and the case fans that were attached started. I'm guessing the power supply is good. Plugged the PS into the MB and touched a volt meter accross the prongs the power supply switch plugs on to. It read 3V. Looks good, right? put the ohm meter to the leads on the power switch and when the power switch is fully depressed, I get no resistance and a closed circuit. It's a soft switch so I'm guessing it only needs to close the circuit for a second to activate the power on sequence. Or it needs current to keep the circuit closed, one or the other, but I'm guessing the power button is okay. I tried putting a jumper on the power prongs on the MB that the power switch attaches to and didn't get anything. I was hoping this would activate the power on sequence, but I got nothing. Anyone have any ideas? TIA

Steve
 

Coyote

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Oct 1, 2003
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Well, if the power button is OK, I'm guessing the mobo shorted to the case.

Take the mobo out, set it next to the case on newspaper or a phone book etc, hook up PS, cpu (with hs+F), ram and vid card and give it a try.

Barton 2500+
Abit NF7-S v 2.0
Maxtor 60GB ATA 133 7200RPM
512MB Corsair Twinx 3200LL
9600 Pro
Enermax Noisetaker 420 watts
Win98SE
 

petriedish

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Mar 26, 2004
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Tried that, no dice. Finally got ahold of a different machine and tried the switches on the other MBs. Still wouldn't power up, so bad MB is what's wrong. Thanks.