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At some point last night we must have had a blip in our power, as the stove clock was blinking like it would had their been... a blip in the power.

When I came into my office this morning, my desktop computer was powered down and would not turn on. Cracking the case, I can see a small blue blinking light on the front right corner of the motherboard. Unplugging the power from the PSU causes the blinking to stop. Plugging in the power causes the blinking to resume.

Pressing the power button does nothing.

Does anyone know what this blinking blue light means?

I'm mostly curious now if it's the motherboard that has gone bad, or the power supply.

I don't have any other desktop parts to use to troubleshoot these components.

Any ideas?

My motherboard is an XFX NFORCE 680I SLI INTEL SOCKET 775 DDR2 ( Model #: MB-N680-ISH9 )

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If pressing the power button doesn't cause the PSU's fan to start up it could be either the PSU or the motherboard. Did you check the circuit breaker on the PSU (if it has one--most do). The power cycle may have only tripped that.

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the PSU is passing some kind of power to the motherboard, as evidenced by the blinking blue light when the PSU is plugged in (just plugged in, no buttons pushed). i don't see a circuit breaker on the back othe PSU, just the power toggle. – Ian Feb 4 '10 at 19:36

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