Mobo won't post. Ya guys gotta help!

jwl3

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Mar 15, 2008
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Hi all,

First off, I want to say that I'm not a noob. I've built 3 computers so far and they've all run smoothly.


Possible factors

1) As I shut down my computer last night, some error message popped up. It was too fast and I wasn’t able to read it before my machine shut down.
2) There was a lightning storm in the area. But I had turned off my surge protector.
3) I’ve been keeping my machine in a tight enclosed cabinet. But I’ve been pointing my fan at the cabinet to exhaust the hot air.
4) My video card has been artifacting like crazy in 3d games but works fine in 2d.

So I try to turn on the machine today. Nothing. Nada. The motherboard won’t post. The DVD light flashes, floppy light flashes, HD light flashes, then nothing. The HD clearly isn’t being accessed and the sequence of flashes is not the usual floppy, DVD, HD, sequence. There’s no signal to the monitor at all. Also, this being a crap Dell, the motherboard doesn't even have leds to tell me what's wrong.

The first thing I tried to do was replace the PSU. The new PSU didn’t change matters. Then I took out the CPU, cleaned the heatsink and applied AS5. Nothing. Checked all the wiring inside the machine. Everything’s plugged in like normal. I don't want to replace the mobo on a 4 year old machine. I might as well buy a new computer.

I mean, I didn’t do anything in between last night (when it worked perfectly fine) and today. I don’t understand how computers can be this fickle.

Help!
 
If your card is artifacting in 3d you should have stopped using/diagnosed it. Even if its working in 2d' there is damage or damage being done to it.

Open the machine and check for dust, clean it all out, put it back together and try again. Its possible the video card died, but the system should beep to tell you this.

If it does not go after cleaning, try to borrow a video card from a friend and see if you can get it to post.

Do you have a motherboard speaker plugged in? without it the board can not beep at you(it beeps out error codes if something is wrong).
 

jwl3

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Thanks. I was about to try a replacement video card tonight. This is the second Radeon 9800 I killed after trying to upgrade to the VGA Silencer Cooler (made by Arctic silver).

I don't have a motherboard speaker. Do you think the motherboard would hang if my video card is toast? I figure that it should post even if I take the card out of the slot.

I suspect the MB more than the video card. On the other hand, I'm not getting ANY type of video signal to my monitor so it might be the video card.

Also am gonna clear the CMOS by removing the battery. I'll post an update.
 

hnml24

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Jun 3, 2008
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Hi
try checking it with a different video card .
if its not working.. guess your mobo was fired..
sorry:\

Best Regards ,
Noam
 

endyen

Splendid
Time to take a long hard look at your mobo. First look to see if the gfx card's fan can spin freely. Now look at the capacitors around the socket. If any of them are leaking, or if the top is not flat, that's your problem - dead mobo.
Next look at the square plastic things by the caps. If any of them look burned or cracked, mobo dead.
Last, look next to where the power cable plugs in. If there are a bunch of solder points (twenty or so), in two rows, with nothing attached, that's because your mob uses a proprietary psu. You could also compare wire color between your old psu and the new one.
To everyone, having a clean mobo helps to diagnose problems, and makes your system run cooler, so keep it clean (well a little pron is ok.)
 

jwl3

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Thanks guys. Do you know if I can replace the mobo without re-installing windows?

The first problem I can see is the chipset drivers being incompatible. The second is that windows activation may invalidate my windows copy because of hardware changes. If you have the cd-key, can you re-activate?