Computer restarting on a whim

[Karroog]

Hey all, I might have the solution for this already, but I just wanted to get people's opinions and try to see if any other alternatives would work.

Background:

I have a desktop computer, isn't it grand!??! 

AMD Athlon 64 X2 6000+ Dual Core Processor
Geoforce 8600 512MB video card
ASUS M2N-SLI Deluxe AM2 NVIDIA nForce 570 SLI MCP ATX AMD Motherboard
Kingston HyperX 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800
OCZ 600W power supply

I think thats enough to get this started...

Scenario:

I'm doing whatever.  It could be playing a game, writing an e-mail, browsing internet what have you.  About a month ago I accidently bumped into my case while trying to get out of my chair.  Didn't think much of it.  However, turning to my screen I noticed the monitor lost signal with the computer.  My brain goes uh oh for a moment.  Basically the monitor said its shpeel of "no signal" then went into hibernate mode.  I pulled out my computer to see what could be the trouble, but right when I pulled it out of its cubby hole the monitor came back on and then it was starting its boot up procedures.

Now this screwed me up big time.  I was not at all sure what was causing this.  A little bump messes monitor up, then I move it a little and its fine again?

I deduced after handling these kinds of this over and over again that my video card cable was screwing up.  It had to have, my video card was securely in the motherboard so I didn't think much of it.

After replacing the cable with a backup I had, I still ran into the same issue.  Ok, I thought, maybe the video card really isn't secure enough in the motherboard slot.  So I switched the video card into a different slot on the motherboard that it could fit in.   Works and all, however now anytime I try to move my computer it does the whole black screen again.

This is getting on my nerves.  I sometimes just slightly graze it and the monitor goes black.  To me, this seems like one connection, either the cable; video card; or motherboard is not secure enough within the case.  I say motherboard because I once tried to plug in a usb flash drive into the back of my computer while I had my computer fully loaded up and it just kicked back to a black screen.  Something isn't secure, but I just don't know how to fix this.  The video card works, I've played many games on it and I believe its just a physical issue in regards to being secured and locked in place. 

Any suggestions of how to somehow get a fix on this would be great.  I'm actually going to home depot cause I lost all my extra screws for my computer and going to get new ones and replace all the screws for my motherboard and video card to see if that works.  Other then that, I'm not sure how else to approach this.

Thanks for any comments you can put in.

[Carbon Dudeoxide]

Welcome to ComputerHope.

Firstly, I would check to make sure the connections from your Computer to the Monitor is solid and connected properly (look for any bent pins).
If you can, try another cable.

Then, if the problem still persists, I would try another monitor (complete with its cable and power plug).

[Karroog]

Welcome to ComputerHope.

Firstly, I would check to make sure the connections from your Computer to the Monitor is solid and connected properly (look for any bent pins).
If you can, try another cable.

Then, if the problem still persists, I would try another monitor (complete with its cable and power plug).

I had thought at first because my monitor had DVI to VGA adapters that it was those that was the culprit, but even switching those out didn't work.  Monitor will probably be a decent place to start.

[Karroog]

Welcome to ComputerHope.

Firstly, I would check to make sure the connections from your Computer to the Monitor is solid and connected properly (look for any bent pins).
If you can, try another cable.

Then, if the problem still persists, I would try another monitor (complete with its cable and power plug).

Maybe I should be a bit more clear...

I thought about the whole changing the monitor thing, and I'm not sure if that would work.  Would a kink in the wire that goes to the monitor restart my entire system?  That's what literally happens.  Sorry if I wasn't clear at the start, but basically my screen goes black and when I get it to working again its back at the beginning of start up, even if I was already in windows with multiple programs running.

[Carbon Dudeoxide]

Oh ok, so the computer shuts down. Sorry I didn't get that part. 

How long has this problem been happening?

Does it still happen in Safe Mode?

[Karroog]

Oh ok, so the computer shuts down. Sorry I didn't get that part. 

How long has this problem been happening?

Does it still happen in Safe Mode?

Man I left out too much information from my original post...

Yes, it still will do it when in safe mode.  I booted in safe mode to be sure it worked with the computer out of my desk, and when I saw everything was working and placed the computer back into the shelf that it goes into the monitor turned off, tried to get it running again by fiddling with the wires and when I did it was back to the startup screen.

This has been happening for a few months now.  It was literally off and on, like a month inbetween but now if I even graze the computer or touch it or move the computer its does it.  Granted if I didn't touch the computer it probably wouldn't do it, but I sometimes need to get behind the computer so I to bring it out of the shelf to get access to it.

[Eg0Death]

Could it be an electrical grounding issue? 

[Karroog]

Could it be an electrical grounding issue? 

If it was then wouldn't my computer be fried already?  It does boot up and work, but if I physically move it, even if its the smallest touch, screen would go black.  I'd have to play with the wires again and then it would restart.

If it was electrical I'd think something would already be dead

[patio]

That vid card hold down screw needs to be replaced...
That is your ground for that device.