I woke up the other day to my MythTV machine being off. When I tried to boot it back up, I got no output.

There is no output to the monitor through the video card. The machine is not pingable. The fans in the machine do turn on (including the CPU fan)...which lead me to believe that the motherboard is not completely dead and the power supply isn't completely dead either. The LEDs on the CDROM do light up, but when I push the eject button nothing happens. Neither of the two hard drives seem to be spinning up.

I've been testing the machine with a brand new power supply. If I plug only the power cable into the drives and power on the computer, the drives spin up. If I plug the power and the IDE cable (going from the motherboard to the drives) the drives due not spin up. I tried this individually on 2 separate hard drives and 1 CDROM and it consistently behaved this way. The CPU fan always turned no matter what I did. The motherboard does not make any beeps or noises and there is still no video output through my video card.

I'm trying to figure out which part went bad so I know what I need to replace.

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Currently running: R5.5, HD5000 x 2, PVR150, Athlon 64 3000+, Chaintech VNF4, 1GB RAM, 2 x 250GB in LVM, MSI NX6200TC -> AA 9A60 -> HDTV

No beeps is bad. Google for POST BEEP and your chipset type.
Unplug everything and see if you can get a beep. If not, you may have a bad MoBo. Try swapping RAM though.
In my case (my main PC died in Sept) it was a bad MoBo, that was killed by a bad power supply. I had an older MoBo that was still good, and killed that one too!
Unfortunately, I always seem to buy whatever is the best bang for the buck, so I can't swap things around as easily (wrong CPU socket, AGP vs. PCIx, etc..). This made it very difficult to troubleshoot by "process of elimination".
FWIW, I now own a power supply tester, which was only about $15 at circuit city.

Hi,

I would suspect the power supply. Unplug it for ~5 minutes then see what happens.

Mike

Do you have any capacitors bulging on the MB? I've seen a few motherboards with bad capacitors that fail to boot like you describe. There are people that will service bad motherboards but it's usually cheaper to buy a new MB.

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Backend R5E50
P4 1.3 - 384MB, 250GB HD, HD5000AV, PVR150 non MCE
Frontend R5E50
EPIA M1000 - 512MB, 40GB HD, Streamzap
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As others have said, probably bad caps.

http://www.badcaps.net/forum/showthread.php?t=649

Seems they use G-Luxon well known for being utterly crap!!!

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DRM 'manages access' in the same way that jail 'manages freedom.'
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Intel P4 2.6
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