RO Other RO + Win+L (Lock) = Gravity Error

I'm having a lot of trouble with this. I really don't have any idea what is causing this problem. Every time I lock my laptop, I instantly get GE'd.

I have a Dell Vostro 3460, running Win 7 Professional 64 bit OS.
i5 3rd gen quad core.
4GB Ram DDR3
Integrated Graphics Card: Intel HD Graphics 4000
Off-Board Graphics Card: Nvidea GeForce GT 630M 1GB

When I purchased this laptop, it came with Win 7 Starter and I did not have this problem. After I formated and installed Win 7 Professional, it started =/