How do I diagnose a (possibly) dead motherboard

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m85476585

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Maybe someone here can help me.

I got home from college today, and I went to fire up my old desktop. I pressed the power button, but nothing happened. The fans didn't even spin up. The blue light on the motherboard (an Asus P5B Deluxe) is on, and the LED on my mouse is on, so it is getting standby voltage. I plugged the PSU into my PSU tester, and it powered up fine. The main voltages are within spec (I got 12.05, 5.00, and 3.29. It's hard to get much closer than that!). I tested the CMOS battery, and that was OK. I tried resetting the BIOS, but it made no difference. I proceeded to start unplugging everything from the motherboard. Nothing happened until I unplugged the ATA cable from the board itself. It was already unplugged from the CD drive, but when I unplugged it from the board, the computer powered up. I plugged my monitor into the video card, but there was nothing. I tried holding the power button, and it wouldn't go off. I turned it off with the physical switch on the PSU, but then I could not get it to go back on. I kept removing stuff until I was down to just the CPU and a single stick of RAM. I plugged it in (with and without the video card present), but still nothing.

The only change I made was swapping out the CPU when I sold a similar computer on Ebay. I don't remember if I tested it then, but I probably did. Other than that, it sat in my room unplugged for the past 4 months. I pulled the board out and physically inspected it, but everything looks OK. There are no (obviously) bad capacitors, and there is no damage to the board or any connectors. The contacts are all fairly clean. I tried re-seating the CPU (Pentium 4 2.8GHz) a couple times, but that didn't help. The board is a few years old, so it is probably out of warranty.

Is there something I am missing, or something I can try to make it work? I can't think of any reason it would just die without even using it.
 

CharlaineC

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sounds like it may have been toasted by a short or a posable lightning strike if it was pluged in. what you are discribing is just what happened to mine when the power substaion was hit by a bolt and the power died. use a meeter and chk the diods neadest the psu and see if any are shot
 

FooBag

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That definitely sounds like a dead motherboard. If the CPU or RAM is fried, generally the computer will turn on, i.e. fan and hard drive spin up, but you will have no video output. The symptoms you have point to a fried PSU or mobo, and given you have tested the PSU already... It might be worth trying a different PSU though just to confirm where the problem is.
 

m85476585

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It was unplugged the whole time, so I don't think lightning would have done it. We do get a lot of static discharge here because it is so dry, so that might have done it, but I am usually careful to touch the metal case before I touch anything else on the computer. I was able to force the power supply on with everything connected by shorting the green wire to ground, and it did everything but actually boot up, so that rules out a major short like a piece of metal across the power pins somewhere. There still could be some other kind of short.

Unfortunately I don't have any components to swap out (CPU, power supply, RAM, etc) since I sold my other computer that was just like this one. I guess I'll have to go ahead and get a new motherboard in addition to the CPU upgrade. I'm considering upgrading to Core i7, but it would be about $170 more and all I would really get is better future compatibility.

This isn't related to my problem, but I noticed that the "copper" heatsinks are actually all aluminum anodized to look like copper. I'm surprised that no one else caught that in all the reviews I read when I bought the motherboard.
 

Donaldsrockets

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Maybe your motherboard is shorting against your case.

One troubleshooting method I heard about in a situation like this is to remove the motherboard from the case and place it on a piece of cardboard or some other anti-static surface.

Then try to turn it on and see what happens.

Also, if you need some good computer advice, check out this forum.

https://www.pcguide.com/vb/

Very helpful and knowledgeable folks.
 

Luv2launch

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Maybe your motherboard is shorting against your case.

One troubleshooting method I heard about in a situation like this is to remove the motherboard from the case and place it on a piece of cardboard or some other anti-static surface.

Then try to turn it on and see what happens.

Also, if you need some good computer advice, check out this forum.

https://www.pcguide.com/vb/

Very helpful and knowledgeable folks.

Yes that works well to check a mobo I use a book like a dictionary to place it on.Then if it turns out it is shorting on the case I cover all the mobo stand offs woth electrical tape, but by the sounds of it its dead if you striped all the drives and such off and it was still not starting.
 

m85476585

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I already tried it out of the case, and it still doesn't work.
 

m85476585

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The new board is on the way (should be here tomorrow), but I just found out that the old board is under warranty. I'll probably keep the new one since it will support a new CPU better (the old board only supports 1333FSB CPUs with a beta BIOS, which would be overclocking the chipset), then sell the old board on ebay for about half the price of the new one assuming they replace it.

I also got an antistatic mat today, so hopefully I won't have any more dead components.
 

Monroe

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You need an oscilloscope to repair a dead board if you plug in a post card (you can buy one) and it displays 00 you will need to go to work. No beeps from the speaker means about the same thing. Most MB's have fuses that look like SM resistors. The number one short is in the peripheral control chip if that’s separate from your south bridge removing it might make the board function. Replacing the oscillator is a good bet as well. With a good microscope you might find a short or burnt component or a sliver of metal. Bad ram or video will do it too right. You removed ALL the cards right?

Monroe
 

Luv2launch

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The new board is on the way (should be here tomorrow), but I just found out that the old board is under warranty. I'll probably keep the new one since it will support a new CPU better (the old board only supports 1333FSB CPUs with a beta BIOS, which would be overclocking the chipset), then sell the old board on ebay for about half the price of the new one assuming they replace it.

I also got an antistatic mat today, so hopefully I won't have any more dead components.
I am running a Asus P5B Vista edition which isn't much different then your board with a 1333FXB chip with no problems at all.
 

m85476585

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The new board is here and it works with all my hardware. I just need to fix the bluescreens (probably a driver issue since I haven't done a clean install of Windows yet). The problem is with gdrv.sys.
 
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Luv2launch

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The new board is here and it works with all my hardware. I just need to fix the bluescreens (probably a driver issue since I haven't done a clean install of Windows yet). The problem is with gdrv.sys.
You were able to get your install of windows to start on a different bnoard without reinstalling?I have only been able to do that swapping out boards with the same chipset on them.
 

m85476585

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It worked, but not perfectly. The hardware was similar, so it might have been compatible enough. The old board was an Intel P965/ICH8R and the new one is a P45/ICH10R. When I booted up and put in the driver disk, it installed all the new hardware like a fresh installation would. All of the old hardware was still listed under device manager, though, and I couldn't get it to recognize the new SATA controller in AHCI or RAID mode; only IDE mode worked (so I didn't have the benefits of hot-swapping or NCQ). The SATA controller problem is related to having to install the drivers by pressing F6 when you install Windows. There is apparently a way to make it work without reinstalling, but I couldn't get it to bot up in AHCI mode without bluescreening. It wouldn't let me remove any of the old hardware either--it said it was necessary to boot the system or something. The bluescreening I mentioned in my last post was actually caused by the overclocking utility for the new motherboard trying to run at startup, so I just disabled it and uninstalled it.

I did a clean installation yesterday, and it is running a lot faster (partly because I put it on my faster disk). It also has all the drivers properly installed so I won't have any hardware issues.
 
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