Hello,
Because Apple doesn't publish schematics or perform component-level repairs in the field, the only repair I have experience with is a complete logic board replacement. I am not sure what chipset is included on replacement logic boards, and I don't remember if there was an Apple Repair Extension Program recall for 2008 MBPs. If there was, it has definitely expired.
Are you experiencing any issues with your MBP?
Sorry I don't have a better answer.
C