I suspect the Nvida is buit into the logic board, I think I would try again for a better resolve.
The nvidia video card is covered whether you have a warranty or not because it is a known issue http://support.apple.com/kb/ts2377 and they will continue to support the replacing of the card, since it is nvidia who is paying in the end.
MacBook Pro owners who bought a laptop with an Nvidia graphics processor in 2007 and 2008 may be eligible for free repairs as part of a settlement agreement for a class-action lawsuit . . . .The affected Mac models include 15- and 17-inch MacBook Pros bought between May 2007 and September 2008. Not every laptop sold during that period is eligible for the settlement—the MacBook Pro models have to contain an Nvidia chip and feature an eligible serial number. (You can check on the former using the About This Mac panel, and confirm the latter on this lawsuit settlement page.) The laptop also needs to be experiencing the scrambled video or blank screen issues.
Message was edited by: leroydouglas
Here is a interesting unconventional fix for some- no endoresement here
I have this same problem with my 17" MBP - Early 2008.
I'm writing from Brazil, so I took my computer to Apple Brazil, they don't want to change the logic board, because they are saying that my computer doesn't show some kind of code needed to send to Apple US to replace the part.
Does anyone know how I can contact Apple U.S. to make this claim?
Sincerely, Alexandre de Carvalho