New artthief, check if you recognize some of your works!! by Nameda on DeviantArt

Arttheft in the huge range :(

Mar 29, 2015 | 18 votes

Mar 9, 2015 | 16 votes

Mar 5, 2015 | 14 votes

Lately more often my monitor screen goes black and then the pc shuts down and restarts by itself
That does not only happen after hours of running (overheating) but more often pretty soon after I started the PC (5 to 20 min)
I have run a full virus scan twice, nothing!
It can't be the HD as that is still pretty new (the old one was failing on me last year and I luckily replaced it before anything was lost)
It doesn't seem to be the monitor, as I can't imagine that the monitor would shut down the PC (had monitor problems with prior monitors, so know the problem
could it be the Graphic card or could it be something else?
Any hint and help would be highly appreciated