my monitor goes off for a second or two at random,any program i'm running, comes back nothing wrong,sound carries on as normal.ran malware and microsoft security essentials,found nothing wrong.is my monitor failing?

Could be. Could be the card (or motherboard, if integrated graphics) too.

There's the obvious first - are the cable connections tight?

Heat can cause this. Is the interior of the computer, including the card, if not integrated, clean of heat trapping dust?

When troubleshooting possible monitor problems, I recommend swapping monitors with another computer. If the problem follows your monitor to PC#2, you know it is your monitor. If your PC does the same thing with monitor #2, you know the problem is inside your computer.