Motherboard won't boot

[jwex2]

I have recently moved my P3 550Mhz to a new case. The problem is the computer now will not boot. The led on the motherboard lights up, the CPU fan spins, the Powersupply fan spins but the screen stays blank. There are no beeps whereas before (when it was working properly) it would beep once as it booted.

After a week of trying it suddenly booted one day, worked for about a week and then died again.

I have tried the video card in another machine and it is ok.
I have reseated the ram and CPU so many time I have lost count.
I have reset the jumper on the motherboard to clear the cmos

I haven't been able to test the ram yet, but as it has two sticks of 128MB PC133 ram and used to work quite happily with either one or two sticks inserted, I feel the Ram is OK as it would be unusual for both sticks to fail at the same time.

What have I forgotten to do? Is the motherboard dead? Any suggestions greatly appreciated
Regards
John

[ski]

See if the monitor works on a different system.
If not, then replace it.

If the monitor is ok, then do a barebones boot with just the power supply, MB, CPU, RAM, video card, and monitor installed, making sure all connections are secure.
If there's a display, then install all of the other cards and all drives one at a time. The last component installed before the problem resurfaces is the culprit.

If there's no display, then place the MB on a piece of cardboard.
If that works, then make sure the MB is not touching anything metal on the case, remove all metal standoffs that do not line up with a MB hole, and check for any loose metal objects under the MB.
If no luck, then install paper washers(a manila folder makes good ones) between the MB and its metal standoffs and screws.

If that does not work, then reinstall everything in the old case.
If the system boots, then the new case may be grounding out the MB.
RMA the case for another one.

If the system does not boot in the old case, then either the PS, MB, CPU, or RAM may be bad.
Either swap them out or have them shop tested to find the bad one.

[jwex2]

Thanks Ski for the advice.

I have removed the motherboard and bench tested it on an anti static bag. It still did not boot so I am thinking faulty motherboard, cpu or ram.

Shall try to test all three in other systems this week

Regards

John

[ziba-june]

Hi John,

Sometimes little things go wrong and we forget to check them. Have you checked the cables to your drives yet?

[Quantax]

And also check if there are any bulging or leaking capacitors on the mobo.

[CyberFly]

your p3 550 slot 1 or ppga? if its slot one just check for chip creap, make sure its firmly seated, cause I had the exact same symptoms on my old p3 500 slot 1.

[matt.matthews1]

I have a question for anyone who can help me. I just recently moved to germany, hooked my PC up and now I get "CMOS checksum error: defaults loaded", I've changed my CMOs battery, and still get the same error. PC will not boot up, can someone help me.

V/R

[matt012]

matt.matthews1 go and post a new topic. This topic is someone else's that is trying to get help.

[matt012]

jwex2 it may be that you have a cable in wrong or backwards. Check the cables to your harddrive, floppy drive, and CD rom.