Arg!! Why won't my computer boot?!?

 Okay, several weeks ago my old motherboard blew up, so I decided to get a new board and processor.

  I installed the new board (an Asus A7N8X-X) with an Athlon 2600 processor.  Everything seemed to go fine.  I booted it up, played with the bios, and noticed that it wasn't detecting my hard-drive.  I changed some settings, restarted it.  It booted fine and would read from the cd-rom drives, but still wouldn't detect the hard-drive.

  I looked in the bios, changed the hard-drive detection back to AUTO, saved and exited.  Now it refuses to boot.  No bios beeps, nothing.

  There's a power indicator LED on the motherboard that is lit, indicating that the board is getting power, but the only response I get from the board at all is if I unplug the power supply, wait, plug it back it and press the power button.  The first time I press the power button after this process, the CPU Heatsink fan gives a weak little buzz and looks like it's trying to start up, but gives up quickly (maybe 1/4 of a second).  Pressing the power button any more does nothing at all.  If I unplug it though, I can get that weak CPU fan try, but that's it.

  I've tried clearing the CMOS several times.  The processor and board are brand new, and the fact that it was working fine initially makes me think they are good.  I guess it's possible the processor failed, but I did a good job with the heatsink and used plenty of good grease, so I doubt it.

  I was thinking it might be the power supply, it's only a 300w, but I tried unhooking everything so just the mobo would draw power and it still won't boot.  Also, if there isn't enough juice, why did it boot the first couple of times?

  Any suggestions would be appreciated, thanks.
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Perhaps the PSU is faulty? you say your last motherboard blew up?
WakeupSpecialist 1Commented:
as stated, may be a bad PSU....however How much thermal grease did you use???  You should only put enuff to cover the die of the chip (the center rectangle only).  And the thermal grease should be less than paper thin.  Also make sure the heatsync is mounted the correct way?  and not backwards (there may be a lip on the undeerside of the heatsynch which should match the Socket lip.
There is a much higher probability of new things failing in their first few hours of use than after they have been running for a while.  It is possible that your motherboard, cpu, or power supply have failed - try to swap one at a time, if you can.
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It is possible that it is your P/S.  There could have been a possiblity that your P/S caused your old MB to go bad.  

>Also, if there isn't enough juice, why did it boot the first couple of times?
P/S can be very strange sometimes.   P/S have voltages that build up inside of them.  So really even if there is not enough to boot there is still some there.
I just thought of something.  since this is a new board are you putting the HD into the IDE slot 1.  I say this b/c there are many boards that have raid devices now.  Raid devices, I believe, are not seen in the bios.  

there is also the possibility that your cable is bad.
JoeMentholAuthor Commented:
AHA!  I found the problem, and it was a dumb one.

I took the motherboard out of the case and it started working again.  Put it back in the case, the old problem started happening again.  I began removing the mounting screws one at a time and trying it, and one screw near the AGP port seemed to be the problem.  I suspect when screwed in it was putting just a little too much pressure on the board and shorting it against the case.

At anyrate, it's working now (hooray!).  Thanks for your suggestions guys, I appreciate it.
That is not an uncommon thing to do.  However, the things that happened to you were different then what I have seen before.   Usually the whole thing will just not boot.

you can ask CS to delete and refund/PAQ your points.


try these steps:

1.Swap IDE cables from a drive which is known working.If after swapping cables the drive works, replace the IDE cable. If nothing happens, disconnect all IDE devices except for the Hard drive, If the BIOS still couldn't detect the Hard drive, there's a problem with the drive.
2.If it's detected, connect IDE devices one at a time until you determine on what device is causing the problem.
3.There's a least possibility of your motherboard to be the one causing the problem because it could detect the other drives. Try swapping IDE controllers. If the hard drive works after this step, replace your Motherboard, controller non-functional issue.
4.Try using a different power cable to the back of the drive, If this works, replace your Power Supply or you could just use a working power cable.
a little late there Mista.
PAQed, with points refunded (500)

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