Crashes with a random coloured blank screen?

It's only happened three times so far, but twice today and I'm worried it might get worse. Every now and then, seemingly at random, my screen will go a random shade of blank (so far, white, beige and black). Everything appears to be working as normal (if I have music on, it continues to play as normal), it's just like my monitor's gone on standby... but in random colours.

The only way to get it to start working again is to restart. Praying it's not my graphics card failing, because I can't really afford a new one.

Any help would be really appreciated

 

My first thought is to install the latest drivers for your graphics card.

 

Another question. Are ye overclocking?

 

I updated the drivers last week and I'm not overclocking.