Sleep of its own accord

[Toothwright]

Not sure if this is the right forum - apologies if it is not.
Briefly - my computer goes into what I assume is sleep mode of its own accord - at any time - last time was when my wife was in the middle of writing an email. Lights stay on on the "box" - mouse and keyboard lights are on and the only way I can get it to start again is to press the reboot button. All Power options are set to "never"

Abit IP 35 pro
Geforce 8800GT
4 GB Ram
Win 7 Ultimate N SP1

I've checked connections etc - the graphics card came out a bit too easily - now reseated - could this be the problem? - it has been stable since then (only 1 hour ago)
As I am now at the "wrinkly" age, the innards are getting a bit of a mystery to me so any suggestions will be greatly appreciated.

Thank you

 

[Grenache]

it's possible that it's hanging, not sleeping.

If you have a second PC, try pinging the first one when it gets into that state to see if it's hung or not.

Does it hang/sleep after a set amount of time, how often?

Try running in safe mode for a while to see if it goes into the same state, just in case it's a video driver issue

 

[Toothwright]

Thanks for reply. - I think you are correct in that it's hanging.

I think its down to a duff monitor, lead or graphics card. Had 2 monitors connected DVI and VGA (via DVI/VGA adaptor). Think it's the latter causing the problem - with just the DVI connection used - no problem. If I then connect the second monitor the computer hangs.

Oh well - I can manage with just the one.