System will not POST after 4 months of Normal Operation?

[Hobo13]

Specs: Asus P5B-E, C2D6400, 7900GS, X-Fi XTreme Music, 2Gig Buffalo Firestix, 1 Seagate Barracuda, XClio 450Watt PSU

My system had been running flawlessly for over four months - tonight I reset the computer after installing some software and now it won't POST. Not just a normal no POST though, nothing so convenient. No signal to the monitor, no beep codes and the HDD light stays on for approximately 45 seconds and then goes off (though I don't here the heads spinning). All the fans spin up and run.

I've tried reseating the RAM, starting with no sticks, starting with one stick, resetting the BIOS (left the battery out and the reset jumpered for 20 minutes, while holding the power button occasionally) and removing additional cards, USB peripherals and the DVD Drive - still nothing. It also appears that USB devices are not receiving power anyway, I draw this conclusion because the Logitech Wireless USB station isn't lighting up at all.

I don't really have any other systems to try different CPU/Mobo combinations - baring that, RMA the mobo or could it be the CPU?

Thank you.

 

[omegatotal]

over clocking? are you running WC or any silent fans?

that sounds like either the psu/mobo is not getting to a power good state or the mobo/cpu is dead...

the hdd light will stay on untill the drive has been reset by the bios, and the lack of beeping means that the board is not even low-level posting yet or stopping very very early at say the cpu test.

pull out the cpu, check all caps on board to make sure their tops are all flat (any rounding out of the average when compaired to the rest of them on the board, indicates a bad cap)..

put the cpu back in maybe try a different psu? or just reseating all the power connectors

 

[Hobo13]

Apologies over the lack of details.

Thank you for your reply.


I'm cooling on air, fans aren't silent - I can watch them spin in any case. I had (oh past tense, why are making me so sad) a moderate overclock @ 2.4 GHz. I did try reseating the power connectors, but I don't have any spare PSU's lying around (I've been primarily on a laptop for the last 6 years).

Would a dead CPU prevent the BIOS from operating?

 

[BillParrish]

yes it will not complete the POST if the CPU is missing or not responding and stop trying to boot.

cpu or mb most likely. Strip the system down to bare essencials. If you dont have any spare parts you can beg or borrow it makes it very difficult. Here is the standard procedure, not sure how much it will help.

ripped off from excellent post by: cozumel
http://www.hardforum.com/showthread.php?t=1144934

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It means that there is a problem but you need to identify the cause.

BEFORE TOUCHING ANY INTERNAL COMPONENTS ENSURE THAT YOU HAVE THE POWER SWITCHED OFF AND THE PSU TO MOTHERBOARD POWER CABLE DETACHED FROM THE MOBO.
ENSURE THAT YOU EARTH YOURSELF AGAINST THE SIDE OF THE CASE BEFORE YOU TOUCH ANY COMPONENTS TO ENSURE THERE IS NO STATIC DISCHARGE

0. Remove CMOS battery for at least ten minutes
1. Disconnect all peripheral devices (router, printers, scanners, external HDD etc)
2. Disconnect all drive cables from the mobo
3. Remove all cards except the graphics from the motherboard
4. Remove all the RAM except for one stick in slot 1
5. Replace CMOS battery
5. Reconnect the PSU cable to the motherboard
6. See if she boots up

-If POST fails then check that RAM and GFX are seated properly in their slots and try again.
-If POST fails again try RAM in a different SLOT
-If POST continues to fail then try a different stick of RAM and try it in slot 1 and do the same procedure.
-If there is still a POST failure check the carefully check the CPU and GFX card to see if there is any obvious damage.
-If they are ok re-seat the GFX, CPU and heatsink and try to boot again.
-If still no POST, remove the motherboard from the case and set it on a non-conductive surface and start again at item 1.
-If there is still no joy then check sniff the air coming out of the PSU from and see if it smells burnt. Do Not Open The PSU - There is seriously life-threatening voltage in there!!

Finally, if there is still no joy take the PSU, GFX, RAM and CPU and try them on a different computer.



Disclaimer: I accept no responsibility whatsever for any damage cause to your components while you carry out any of the above procedure. By following this procedure you accept liability and responsibility for any damage caused

 

[Hobo13]

I RMA'd the mobo. My gut instinct tells me that its that rather than the PSU or CPU - I'm blaming the hot as hell northbridge. I'll check the rails on the PSU with a voltmeter though. While I don't know if the Conroe is different, when I've had a dead CPU (as opposed to a dead mobo) I still get a little bit more feedback than what I'm getting.