Display goes into standby during games etc

[Steve_45]

While using my computer (sometimes even while typing on facebook, my monitor will go into standby mode until i move the mouse or tap the spacebar - then it goes back to normal, this is intermittent and can happen after 10 mins, 3 mins or even 30 minutes, my power settings are set so that they NEVER turn off

Running windows 7 home premium

 

[Steve_45]

can someone please help? im at my wits end!