# [SOLVED] No signal to monitor, random restarts



## Reiik (Sep 30, 2011)

So, recently my monitor for my desktop PC started not coming on when my computer was starting up. It wasn't so bad at first, I would restart the PC once or twice and it would finally kick on. Then it happened when my computer went idle (as in, I left it alone for a while and the screen went blank as is normal) and no matter what I tried I couldn't get the monitor to fire up with the computer.

I must've restarted it 20 or 30 times, and I noticed occasionally that I would turn it on and then after a few seconds the PC would shut off of its own volition without me hitting anything. It didn't do this all the time, it was pretty infrequent in fact. It's entirely possible that in my spamming of the power and reset buttons (slightly frustrated) I hit the power button when it was already coming back on and there was just a delay before it shut down as a response. I can't say for sure, though, and the same thing has happened a few times since.

It's worth noting that part of my PCI-E slot is broken - I was trying to pull the card out for something a while back and in the process I somehow managed to break the little piece on the end that locks the video card in place (the piece on most mobos that you have to press to release the card). The card is screwed in at the back of the PC, though, so it sits just fine. I thought it might have dislodged, though, so one time while the PC was spinning I reached in and jiggled the card around, and voila, instant signal to the monitor. That didn't last though, and adjusting it like that hasn't ever helped again.

I was going to try replacing things when I thought to check the DVI cable. I replaced it with a borrowed one from a friend and everything worked great. I even noticed that the one I had been using had several depressed pins, so it seemed like a likely culprit. I ordered a new DVI cable, got it today, and plugged it in. And there was no signal to the monitor. I should say that I'm reasonably certain it's not the monitor, when I remove the cable from the PC the monitor says "Check Signal Cable" instantly, and it stops when I plug it back into the PC. I also have a PS2 hooked into the monitor's component input and that always works fine, even when the monitor/PC connection is having problems. I would check it with another PC or monitor had I a convenient way to do so (if needed I could buy a VGA / DVI adapter and plug my laptop in, but I really don't think it's the monitor).

So, after some more frustrated restarting with the new DVI cable, I got video signal. I don't know how long it's going to last, though, so I want to get this fixed. Ordinarily I would just blame it on the video card (8800GT, about 3 or 4 years old), replace it with something newer and better and be done with it, but the random restarts has got me worried that it might be a PSU problem. Also, I've never really heard of a GPU dying with symptoms like this, so I'm just not sure what to think, and I can't really afford to replace GPU and PSU in the same timespan. I'm also wondering if the broken connector on my board means that the GPU is just dislodging itself, and if I need to replace my board. Sorry for the humongous post but there's been a lot involved with this. I've done my own maintenance for years now but this is just so random I don't know what to think, any thoughts (or even anyone who takes the time to read all of this) are greatly appreciated.


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## JimE (Apr 16, 2009)

*Re: No signal to monitor, random restarts*

Shutting off or restarting on it's own?

Shutting off is usually an indication of a hardware issue. Typically with the power supply or motherboard.

Restarting can be a hardware or software issue.


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## Reiik (Sep 30, 2011)

*Re: No signal to monitor, random restarts*

Both, actually. When it shuts down, sometimes it stays off and sometimes it fires back up after a couple of seconds.


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## JimE (Apr 16, 2009)

*Re: No signal to monitor, random restarts*

Sounds hardware related, likely the power supply or motherboard as noted above.

You can pull it apart for testing, there is a guide here> http://www.techsupportforum.com/forums/f15/how-to-bench-test-troubleshoot-your-system-262998.html

Your hardware specs would also be helpful.


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## Reiik (Sep 30, 2011)

*Re: No signal to monitor, random restarts*

Board: ASUS P5Q SE PLUS LGA 775
CPU: Core 2 Duo E8500 Wolfdale 3.16GHz
PSU: SIGMA FOCUS SP600B 600W
GPU: NVidia 8800GT

I assume hard drive / memory info aren't really relevant for this.

*EDIT:* Didn't mean to post that just yet. I won't have a chunk of time in the next few days to disassemble my tower all the way, but if in a few days things are still being weird without a clear answer I'll definitely give it a shot. And yeah, PSU sounds right except for that bit about nudging the video card and getting signal, that's still got me puzzled.


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## Tyree (May 10, 2009)

*Re: No signal to monitor, random restarts*

All specs can be relevant but that low quality PSU stands out as the most likely problem.


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## Reiik (Sep 30, 2011)

*Re: No signal to monitor, random restarts*

OK, that makes sense. Could you recommend a brand of PSU that tends to be better quality?


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## JimE (Apr 16, 2009)

*Re: No signal to monitor, random restarts*

There is a guide here> http://www.techsupportforum.com/forums/f210/power-supply-information-and-selection-192217.html


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## Reiik (Sep 30, 2011)

*Re: No signal to monitor, random restarts*

Just to wrap this up - in the end it turned out to be a combination of a busted DVI cable and a failing power supply. Replaced both components and things are running great. Thanks so much!


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## dai (Jul 2, 2004)

*Re: No signal to monitor, random restarts*

glad you have it sorted


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