Perhaps you just need a new Video Card. They are not hard to install.
Now what your saying sounds like it's a bad Video Card.
Just make sure you buy the right kind.

http://www.nvidia.com/object/geforce_8700M_techspecs.html

PCI Express® x16

DIAMOND 3650PE1G-PB-R Radeon HD 3650 1GB DDR2 PCI Express x16 HDCP Ready Video Card. It is a Refurb but only $50.00. It's the only one
of the x16's with a gig of ram. I often buy reburbs and most of
the time they are like new.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814103209

Here's some at Tiger Direct:

http://www.tigerdirect.com/applications/Category/guidedSearch.asp?CatId=28&sel=Detail%3B55_158_76437_76437

That Refurb at NewEgg looks like the best deal.