Solved Passes POST but no boot up or monitor input

June 11, 2011 at 19:01:49
Specs: Windows Vista 32
I was playing a game when I got a freeze with sound looping. Can't get it to boot up after that.

Upon turning on the power it seems to past POST (single beep) but I never receive monitor input. Don't get any hard drive activity either.

Tried replacing and swapping out RAM, replacing graphics card, removing graphics card to use integrated. No luck.

Removing CPU, RAM or hard drives completely stops it from passing POST (no beeps). Same if I disconnect hard drives, connect DVD drive with boot disk.

USB ports are all powered, as are fans. My aftermarket CPU cooler runs for a second or so and then stops, but my stock fan runs as normal. Graphics card fans remain on full power (usually tones down after booting).

I suspect something's wrong with the motherboard, power supply or CPU, as everything else has been replaced or removed to no effect. Is there anything I can do to narrow it down further? I don't have any spare units to test with.

My specs:

Q6600 G0 with Hyper TX3
2x2GB Kingston DDR2 800MHz
Gigabyte GTX 460 OC
Maxtor 320GB and WD Caviar Green 1.5TB
Corsair VX-450
GA-73PVM-S2H


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✔ Best Answer
June 16, 2011 at 02:44:44
There is no way to know if the CPU has been damaged or not. Inspect the under side of the board for additional damage. If not found you can try reusing the CPU. Never heard of a fried CPU damaging a new board.

You MAY need to perform a repair installation of Windows when things are put back together.

Up in #4 above you mention upgrading to newer processor and board. You will probably need to get new DDR3 RAM too.



#1
June 11, 2011 at 19:39:32
Your 460 can draw 23A @ 12V.

Your CPU draws another 8/9A

Your entire 12V rail only puts out 33A

Add in the drives, fans, etc.

You need a better PSU. Probably burned out the 450.

http://www.newegg.com/Product/Produ...


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#2
June 11, 2011 at 21:54:55
Thanks for the quick response. I'd been running comfortably with that setup for a few months but the PSU is 3 years old. Are the signs I get when trying to boot also symptomatic of a PSU failure?


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#3
June 12, 2011 at 06:04:36
Try booting into Safe Mode. That takes less power because the graphics are just VGA.

You also could have damaged your graphics card.


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Related Solutions

#4
June 12, 2011 at 17:15:27
I cannot boot into safe mode as it never gets to the BIOS screen - no monitor input or hard drive activity. I've tried with graphics card removed to force onboard, but that doesn't change anything so I suspect it's okay.

Edit: also tried with a 9600GT. No change.

Barring any other suggestions I'm going to buy a better PSU tomorrow. If it's a motherboard or CPU failure I'd need a new one anyway, seeing as it's probably time to upgrade from LGA775.


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#5
June 14, 2011 at 15:56:17
New PSU didn't change anything. I've heard that CPUs don't tend to die, can I be fairly sure that it's the motherboard?

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#6
June 14, 2011 at 19:29:46
Is all your hardware being configured at start up by the BIOS? Things like a defective optical drive, for instance, can prevent booting. Disconnect all external devices that are not necessary to run. Check card readers for media and remove.

What is the brand and model of the replacement PSU?


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#7
June 15, 2011 at 00:40:50
New PSU is an 'Antec Truepower' 750W.

I've tried running with nothing but the boot drive attached, and nothing but the DVD drive with my Vista disk. Same (no) result for both. Hard drive spins up and the DVD drive opens but it doesn't sound like anything is being read.

One thing that changes is that while I get the POST beep with the hard drive attached, there are no beeps with just the DVD drive.


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#8
June 15, 2011 at 05:28:07
You don't need ANY drive attached to POST. Try removing the motherboard from the case and use ONLY the following items. Motherboard with CPU, HS/fan, 1 stick of RAM, Power supply connected to the motherboard, keyboard, monitor, graphics. No case to board connections, no other external or internal connections or cards.

Clear the CMOS by removing the battery without any power connected.

Start the board by momentarily shorting the power pins on the motherboard. Immediately try to enter the BIOS. If no video with on board, try the add in card.

If you have a PS/2 keyboard connector us a PS/2 keyboard.

This is the most basic configuration you can have. You should get 1 beep at start up. Removing the memory and starting should give you a memory error which is different than the 1 beep.

Try all monitor connections. Don't use HDMI. Want to use VGA.

If no go, then try another add in graphics card. PCI if you have one. I don't think you would hear the single beep if the board or CPU were bad.


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#9
June 16, 2011 at 02:02:16
Removed motherboard. Nothing attached but graphics card, 4 pin and 24 pin power connectors, CPU + fan, 1 stick of RAM and keyboard. No beep, no input.

Tried onboard graphics as well as different RAM and ram slots. No difference.

Get the single beep if and only if my boot drive is plugged in - even if there's no RAM, the 4 pin ATX12V is unplugged or if the CPU has been removed.

Also, when replacing the battery I discovered this:

http://imageshack.us/photo/my-image...

One of the... square things seems to have failed and it was sooty all around. Would it be safe to assume that that is the source of my woes, and that a new motherboard is the solution? I don't suppose there's much chance that the CPU has been fried as well?


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#10
June 16, 2011 at 02:44:44
✔ Best Answer
There is no way to know if the CPU has been damaged or not. Inspect the under side of the board for additional damage. If not found you can try reusing the CPU. Never heard of a fried CPU damaging a new board.

You MAY need to perform a repair installation of Windows when things are put back together.

Up in #4 above you mention upgrading to newer processor and board. You will probably need to get new DDR3 RAM too.


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#11
June 16, 2011 at 04:33:59
No other visible damage or burns on the underside of the board, but after confirming that the POST has no relation to the status of the CPU I'm starting to suspect I might have cooked it myself when I first powered on without knowing that my fan wasn't functional.

Oh well. I'd been eyeing that 2500k for a while anyway.

Thanks for the detailed and helpful responses OtheHill.


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#12
June 16, 2011 at 06:52:31
Well, the outcome isn't what you had hoped for. Thanks for getting back with results.

I suspect the underpowered PSU may have had something to do with things. If a CPU fan is not running or running slow, there are safeguards built into the CPU that prevent it from frying.


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