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I'm having a serious problem with my computer; I think I've narrowed it down to the motherboard, but I'd like a second opinion before I spend the money. I have no idea what's wrong.

Before I moved into my new apartment, my desktop was working fine; now, it just won't work. It will turn on, the fans will spin up, lights come on... but nothing appears on the screen. No POST, nothing. I've tried:

  • A different monitor (both are VGA)
  • A different video-card (both are DVI, PCIe)
  • Three different, known-good VGA->DVI adapters
  • The onboard video port (VGA)
  • Reseating the memory, and trying only one stick
  • Different, known-good wall-outlets
  • Unplugging the HDD and CD-drive from both the motherboard and PSU
  • Replacing the PSU
  • Replacing the motherboard
  • Taking the motherboard out and running it on a piece of cardboard

Has anyone had this happen before? Any advice!?

Here are my specs:

  • A13G+ V3.0 motherboard
  • 2 2-gig 800mhz DDR2
  • 600-watt PSU
  • two older Geforce video cards
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7 Answers 7

up vote 3 down vote accepted

Having had this happen to me recently - if the fans turn but there's no beeps even when you remove all the memory modules then it's the motherboard that dead.

The fact that the on-board video doesn't work would lend more support to this theory too.

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Well I just replaced the motherboard, still nothing. –  BlueRaja Mar 16 '10 at 1:46
2  
Bought a THIRD motherboard, now it works. –  BlueRaja Apr 27 '10 at 14:03
    
Try to replace ram!! Like I did :) –  Little Helper Aug 3 '11 at 18:46

It certainly does seem like the motherboard is having difficulty, but don’t chuck it out just yet. (My motherboard is working just fine because I have a hunk of wood jammed in behind it to address the broken lead in one of the internal layers, I am using my mouse/keyboard in USB mode because the PS2 connectors have cold-joints, and I have a piece of plastic bowing the board to keep the RAM modules correctly connected.)

Anyway, you mentioned that you recently moved. Presumably the system was jarred somewhat in the process. Try re-seating the CPU. In fact, take this opportunity to re-seat everything, making sure to clean all connectors (specifically if the system has been in use for a year or two). You can clean the patinas off with a soft, rubber eraser or an alcohol dipped cotton swab. Make sure to clean and re-seat the cables as well.

Finally, even if it doesn’t seem to work, try coming back to it later since sometimes a problem is of the worst variety: not just intermittent, but occurs once out of nowhere, then disappears without a trace. While they are debugging-ly terrifying, they are also a relief once they are gone and haven’t come back in months. ;)

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Well tried that, replaced the mobo too, still nothing –  BlueRaja Mar 16 '10 at 1:44
    
+1 for keeping a mobo that needs to be taken out back and shot running ;p –  Journeyman Geek Mar 16 '10 at 3:59
    
With a motherboard like that I'd just try to do some hand resoldering.. Whats the worst that can happen? –  Earlz Apr 22 '10 at 16:01
    
@Earlz, (1) I could kill it and then I’d be left without a working computer (though I could use an older, inferior one I still have that has its own probelsm). (2) Soldering won’t work since the motherboard is a multi-layer PCB and the problems are internal. (3) Recently a piece broke off of the board next to the NorthBridge when I was trying to clean the dust off. I managed to sort of solder it back on (thankfully the leads were on the sides, not under it), but I’m not sure how well it is connected since it can easily wiggle. –  Synetech Apr 22 '10 at 19:59
    
For the record, that board permanently bit it (no amount of fiddling or force could get it to POST anymore) in the last week of October 2010. I spent the next six weeks without a computer until I found a decent used computer I could afford. I’m not throwing it out though because it was such a great board with great features (an EPoX). The point is, that it didn’t fully die until ~5 years after the initial problems, and almost a full decade after I bought it. Computers are still much more resilient than people tend to think. –  Synetech Feb 28 '11 at 0:35

Dude, is it possible that your motherboard is grounding to the case? Did you install those little standoff studs?

http://www.amazon.com/Motherboard-Screwnut-Standoff-50-PCS/dp/B00008VF6K

Yknow, those things?

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You're right, I didn't have any of those. However, testing it on a piece of cardboard, it still doesn't work (either of the mobos). Could that have broken them? –  BlueRaja Mar 16 '10 at 23:17
    
Wait no, this case doesn't need standoffs, the holes are raised. –  BlueRaja Mar 19 '10 at 2:31

If you think it is specific to the motherboard, the exact manufacturer and model would be helpful. Is it PC Chips A13G+?

Are there any beeps during when POST should be running? This will be via the PC speaker or buzzer. Not all modern systems include them anymore.

For dual-channel DDR2 you need to keep two (2) DIMM modules installed.

I'd suggest remove both video cards and using the on-board video, until this is resolved, unless you think the on-board video may be disabled.


Added:

By removing both graphics cards, I want you to try the simplest possible configuration that could boot at least as far as the BIOS. This would include removing any optical drives (CD/DVD), hard drives and external devices. Just a power supply, motherboard, RAM (two DIMM modules), and CPU (with heatsink of course), and trying to the use the on-board video.

Personally, I often remove the motherboard from the case at this point, that is merely personal preference. That is to isolate any potential short-circuits either caused by the case and the motherboard itself, or a dropped screw lodged under the motherboard for example.

I believe that if there are no POST error beeps, then most likely the CPU has failed, or the motherboard has been damaged.

Because it is difficult to determine which is the cause, it might be best to simply replace both the CPU and motherboard, and reuse the other components. There is a small chance that if you try replacing the wrong item, the damaged component could damage the replacement part as well, so that is the other reason I recommend replacing both.

I'm sorry I don't have any further insight. From your description, you have done a good job trying to isolate the problem.

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The on-board video does not work either –  BlueRaja Mar 12 '10 at 1:41
    
Well I replaced the mobo, still nothing; I will try running it outside the case. Could a bad processor really cause this? –  BlueRaja Mar 16 '10 at 1:45
    
Yes. Overclocking and over-heating are the two major causes for a processor to fail in-place. –  mctylr Mar 16 '10 at 13:00

If this was me, I would say my next steps would be to unplug the power then remove the battery on the motherboard.

Remove all devices and add-on cards then after about 20 minutes plug in just the keyboard, monitor to onboard video and the power.

If you still see nothing, double check that there is no conductive junk touching any jumpers - but at this stage, If you haven't even heard any beeps (working or non working ones, it isn't looking very good for the board and I would probably say it is dead.

... It could be something simple like a problem with the PSU, but it is very unlikely.

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replaced the PSU, and mobo, and did all those other things, still nothing. –  BlueRaja Mar 16 '10 at 1:44
    
@BlueRaga so you got a different motherboard in the machine and it still didn't work!? –  Earlz Apr 22 '10 at 16:03

Random thoughts :

  • Have you tried using a different power cord? I know you mentioned using a different PSU and different wall outlets, but maybe the cord developed a kink/break as you were moving. (Low odds, I know, but if you're grasping at straws...)
  • Check the motherboard's jumpers and make sure everything is in order. Again, low odds, but if a jumper happened to slip off as you were moving the case around, that might explain what you're seeing. (I'm thinking maybe the 'clear-settings' jumper popped off for example..)
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Just plainly by the fact that you've tried everything else, try taking it to a friends house (that has a computer that runs at their house) and try running your compute at their house and see if it works.

Judging from that you've done everything to locate the problem including replacing the motherboard, and it still doesn't work, I'm going to venture to say that your new apartment may have very serious wiring problems. Maybe the grounds aren't actually grounded or it is reversed polarity, or both!

But yea, if your computer works at a different house, then it is definitely something to do with the wiring of your apartment and you should have a qualified electrician(read: not apartment staff) come look at the wiring.

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