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PC won't power up - no fans, but power LED lights

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Ghost072

MIS
Jul 30, 2001
4
US
The only thing that shows life is the power LED. Besides the power supply, are there any other possible causes? I've thought of a short (the risers the MB rests on are metal, but they appear to be lined up properly). Also, does the CMOS battery supply power to the power LED? Seems strange that this would be the only sign of life if the PS is bad. Thanks in advance...
 
Take it to the bare minimum of cards and connectors. This sounds like a classic case of permanent reset.
Also can fail like this with ram problems and cpu problems.Speeds and voltages can also affect the processor.
PS is power led source. Battery is CMOS only. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 
I've never heard the term "permanent reset;" what does that mean?

Speed and voltage is set in BIOS for this board, but I can't get in there yet.

It's an Intel 810, so I'll take it down to just power to motherboard tonight. But, if the problem persists, should I replace the power supply?
 
it's most likley not a PS problem I don't suffer from insanity, I enjoy every moment of it.
 
Permanent reset is when the reset switch shorts shut or the keylock switch is connected to the reset pins. Or the reset pins get bent and short together. Anything that keeps the M/B in reset.
I don't know the M/B. AT or ATX form factor? If ATX you also have to short a power on set of pins to bring power up.
Minimum would be power connector, power switch if ATX, and video card if not onboard. This in theory gets you to video post splash screen. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 
The MB is an ATX INTEL 810 (onboard video). What pins would you need to short (I know you're working blind, but would it be the RST SW jumper switch)?

Thanks for all you help...
 
No, those are the 2 that if shorted will keep the board in permanent (as long as they are shorted) reset.
Generally somewhere near the atx power connector, usually with a plastic guide, may be labeled as power, may be marked as on/off. Haven't seen any with power switch near the other offboard connectors, but that relates more to my lack of atx experience. I'm sure there will be manufacturers that will run the traces to the edge of the board. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 
A power supply can be bad and still light up the LED's. I have had this happen before. It is worth it to have a technician check the power supply. I have no idea how to check a power supply? It is probably a really simple process. Using a voltage meter or something like that. Of course when you are playing with 110 V you wouldn't want to make a mistake.
 
We had this problem when I installed my new ABIT motherboard not to long ago. Make sure that the proccesser fan is connected to fan 1 on the motherboard. Some boards do this as a precautionary measure. If its not on fan 1 it will not boot!
 
As it turned out, a mounting screw was causing a short in the floppy drive. Once I removed that screw, everything came up fine. Never seen that one before!

Thanks to everyone who offered suggestions...
 
I haven't seen it either but NOTHING suprises me anymore. I had one short out when one particular case screw was put in!!!! Every day above ground is a GOOD DAY!!!
 
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