Computer won't boot AT ALL...dead mobo?

enisei

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Jan 13, 2010
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18,510
Greetings,

I am posting this problem of mine in the Motherboard category because I believe at this point I have a dead motherboard but I need some reassurance and/or advice on if it is in fact a dead mobo, before i go out and purchase a new one. Here is my problem....

Approx 3 days ago I was running a computer game and suddenly my computer froze. No ctrl-alt-del, no cursor, nada... So i reset, booted back up and things appeared to run fine again. 1 day ago, playing a completely different game (browser based so its nearly resource free) and computer freezes once again. No ctrl-alt-del, no cursor, nada...So i reset. Computer boots up and for about 2-3 minutes things seem fine. Then, frozen again.

So i reset again, except this time I get to the POST screen and it starts to show my drive list and it freezes again. No cursor, no ctrl-alt...you get the picture. So i physically reboot once more, except this time I get NOTHING. No beeps, no screen, nothing except total darkness. As of this time, I cannot get ANYTHING to show on my screen...just total darkness...No POST, no cursor, NOTHING.

My computer does turn on, fans all kick on, power light comes up, but nothing on screen. In trying to troubleshoot over the past day, I have done the following:

-Blown out all dust with compressed air and cleaned it thoroughly.
-Removed heatsink and fans, cleaned off old thermal paste and reapplied new paste.
-Installed a new video card from the store very similar to my current card.
-Hooked up monitor to Cable tv box and showed picture just fine (its not a monitor issue)
-Tried alternative DVI slot on video card.
-Removed 4 sticks of ram, and tried 1 stick in each slot seperately.
-Checked all MOBO connections and wiggled things around to make sure no short present.

For what it's worth, I had a video card die on me back in Feb' 2010. I purchased a brand new Sapphire ATI Radeon 5870 and it's been running FLAWLESSLY from Feb up until 3 days ago. Combine that with the fact that I have also tried a BRAND NEW video card from the store today, I am heavily leaning toward it NOT being a video card issue.

That leaves me with only one conclusion....fried motherboard. With all that being said, is there anything else i can try in order to make anymore eliminations: ie. power supply, cpu, ram, etc. or do all arrows really point toward the mobo being done?

If it was the cpu, i should at LEAST get to post right?
If it was the power supply, wouldn't all my fans (approx 10 of them) not operate?
If it was a ram issue, wouldn't that have been solved by individually trying each stick as i did?
If it was a video card issue, the brand new card should have displayed something?
If it was a harddrive issue, I should at least get to POST bios?

Lastly, I will list my components as to hopefully help out as best I can to explain my dilemma... Thanks for any and all help!!!

Gigabyte GA-P35-DS3R Motherboard
Intel Q6600 cpu
Crucial Ballistix 4 x 1 gig sticks
OCZ GXS700 power supply
Sapphire ATI Radeon 5870 (or Radeon HD 5770)
Auzentech Sound Card (disabled on-board)


****UPDATE 06/20/2010 @ 01:00*****

So i post this message, return to the skeleton of my computer and start putting things back in place to leave it sit until I can find a new mobo (or upgrade entirely) and wouldn't you know, i give it one final shot and it comes up and works as though it never missed a beat....

Needless to say I am not convinced the problem was "solved" necessarily and I will be wary for the next few days, but as of this moment I am updating any and ALL drivers to make sure I am as up to date as can be. I'm not sure what may have caused it to come back to life (maybe the threat of an upgrade), but as of writing this update, it's running. I'll keep posting for the next few days to make sure it doesnt die again, or if it does, maybe I could continue to get a little support until I finally solve the issue.

****UPDATE 06/20/2010 @ 01:53****

Sooooo, i updated to the latest ATI drivers, rebooted and everything appeared to be running fine for 30 minutes. Around 0150 hours, i was browsing the web and suddenly the screen just go black. The computer itself didnt make any strange noises, didn't appear to reset, and did not power down. The screen just went black, no warning, no artifacts, no lines, no delay or pauses, just one second everything is fine, the next the screen is black. Now the system will not boot up and continues to give me black screens, no POSTing. Help?!
 

dooodo

Distinguished
Jun 12, 2010
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18,530
Dead mobo symptoms imo. Same thing happened to a friends pc.

Edit:
Try getting another psu though, as it may have died. I've seen bad psu's power on fans and not have enough power for the rest of the computer.
 

No. Dead CPU will not run the POST code.


Not necessarily. Fans use very little power. Besides, fans run off 12 volts. You could have a problem somewhere else in the PSU and fans would still work, but nothing else would.


Should have been.


Yes, unless it was bad. Simple thing to do here is test them in another (working) computer.


Yes, unless you have a bad drive shorting out the PSU, but that's unlikely. You do not need a hard drive to POST.You also do not need a keyboard or mouse.

Our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

Suggestions about how to check your PSU:
Try to borrow a known good PSU. If you cannot do that, borrow a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. The CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.
http://www.youtube.com/watch?v=5FWXgQSokF4&feature=youtube_gdata

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

If you have worked through the checklist, and have been unsuccessful, try breadboarding (building the computer outside the case.

Breadboarding - that will isolate any kind of case problem.
http://www.tomshardware.com/forum/262730-31-breadboarding

I have a paragraph in the breadboarding thread about building and testing a PC in stages.

And last, do you have a system (case) speaker installed? If so, what are the beeps? If not, you really need one.