My screen is showing squares[HELP]

[masterball63]

I'm getting all these squares on my desktop, when playing games, everywhere!

http://www.dropbox.com/gallery/12971823/2/Freshly%20Fraps-ed/Broken%20Stuff?h=7544d8

I took screenshots of my problem.^Link Above^

I have an i7 840QM
Nvidia GTX 260m
8GB RAM

They appear in two of my games
Games I play: Starcraft2. CoD:MW2. CoD:BO. BFBC2
The squares appear when I turn in Windows Aero, when I play BFBC2 and CoD:BO
Never happened with SC2 and MW2.
Is this a software or Hardware problem?
I have tried doing a clean reinstall of my Nvidia Drivers.
Any help would be greatly appreciated, thanks.

 

[Tamz_msc]

It could be an overheating problem.