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General discussion

ASUS P4P8X not POSTing after shutting down

Sep 7, 2004 5:06PM PDT

I turned off my computer earlier today and when I came home this evening my Computer would not start... it will not even post, the CPU fan spins, the light on the MB is on, my video card fan spins, blah blah blah, just no post, HD is spinning also.

The computer worked fine, so I'm not worried it's a problem with any of the hardware, I dont see how I can fry something by simply shutting it off.

I took the MB out and set it up on cardboard to see if there was a short, still has no effect.

I also tried resetting the CMOS (I think) and it had no effect either...

Any other suggestions short of trying a new CPU or motherboard?

Current OS: XP
CPU: Intel P4 2.40
Video card: GeForce 4 Ti 4200
Power Supply: AOpen ATX 300GU

Discussion is locked

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Why the small power supply?
Sep 7, 2004 11:04PM PDT

You can try removing "extra" parts like CDROM/DVD drives and whatever else (floppy?) to free up some Watts. That power supply was typical for the under 1GHz crowd.

Bob

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No help here, BUT
Sep 7, 2004 11:13PM PDT

you should learn that the transient spikes that CAN occur at turn off of anything can do more damage than the simple high inrush currents related to turn ons.

Except for tungsten filament light bulbs which normally blow at turn on.

Why you don't suspect hardware is beyond me.

There are many possible causes. I'll give one because you seem to have the voltages.

The light on the mobo is simply the 5 volt logic power that is always there as long as the power supply is plugged into an AC line. Matters not whether the system is on or off. The other indications are for the rails that provide power after turn on.

I mention this [not usual] one because it happened to me recently. At power turn on the power supply voltages must rise from zero to the desired level. To prevent malperformance during this period the master reset is held on by a logic level from the power supply. The power supply delays a few hundred milliseconds to let the voltage stabilize and then releases the master reset line which then starts the booting process. The specific signal from the Power Supply is Power GO or Power OK. If this never releases you can have all of the voltages up and in spec and still will not boot.

As I say, this is only one of the many possible causes.

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Addendum. Is the BIOS current?
Sep 7, 2004 11:27PM PDT