Help! screen turns black randomly

[poisonblade11]

My computer randomly turns black and the monitor says no signal, but I still hear sounds and such so the computer is still on.
The problem isn't the monitor because I tried all the connections and the monitor works fine with a different computer.

I think the problem may be the PSU or the video card, but I doubt it's the video card because I got it only 4 months ago.

Also sometimes the screen turns black, but slowly recovers by showing the taskbar slowly and the whole desktop eventually, with the cursor lagging on the screen and teleporting to places.

Specs:
Windows 7 64 bit
AMD Phenom II x 4 955 Processor, 3.2 Ghz
AMD Radeon HD 7700 Series
4.00GB Dual-channel DDr3 @ 666Mhz
Asustek Computer INC M4A79XTD
HD DVD Writer 1260d ATA
Rocketfish 700w psu
465GB Western Digital WDC WD5000AADS-00S9B0 ATA Device

 

[scout_03]

try your gpu in the second pci-e slot to test the system for black screen .

 

[Shaun o]

If the temps of the 7770 card seem fine and not to hot.
Then you would conclude the Psu was to blame.

By that I mean if the black screen does not happen when using the pc in normal desktop mode.

But always results in a black screen when playing any game that requires the video card to use more watts and amps from the Psu.

Also alter the power scheme of windows just to check it`s not a fact of sleep mode engaging as part of power saving and causing a driver to halt or crash forcing it to restart.

 

[poisonblade11]

The screen turns black randomly, not just when playing games.
But yeah I'll try putting my gpu in the second slot, and my power options are fine.

 

[scout_03]

does the screen work without been black in the second slot .