Thanks for the response. I've seen that page, and it's precisely why I'm confused--though my MBP was manufactured in September/October 2008 (month seems to vary based on which serial number info service I'm using), it's referred to as a "MacBook Pro (Early 2008)"--see my pasted serial number results below--which would seem to indicate that it falls within timeframe of the NVIDIA problems. I just don't understand why having the 2.5GHz processor instead of the 2.4 would affect the GPU. Any enlightenment would be much appreciated.
Serial number: ---Removed for security reasons---
Name: MacBook Pro (Early 2008)
ModelCode: mbp_early_08
Model Number: MB134
Group1: MacBook
Group2: Pro
Generation: 41
Machine Model: MacBookPro4,1
Model introduced: 2008
Production year: 2008
Production week: 40 (October)
Production number: 14248 (within this week)
introduced test: GOED
CPU speed: 2.5GHz
Family name: A1260
Screen size: 15 inch
Screen resolution: 1440x900 pixels
Colour: Aluminium
Memory - flavour: DDR2-S-667
Factory: W8 (Shanghai China)