My late 08 Macbook Pro is currently having brain surgery for a defective 9600GT. I also have seldom used the 9600GT (maybe 4-5 times) since buying the computer, and 24 hours after switching it last week, it locked up and gave me distorted graphics in safari.
FWIW my machine's serial number comes out as a week 46, but when they hooked up the displayport tester at the genius bar, it showed a manufacturing date of week 25. This may be the actual date of the display port and thus logic board manufacture, which is months before the machines were built, so take that as you wish; probably one of the earliest unibodies with the crap leftover NVIDIA garbage.
FWIW my machine's serial number comes out as a week 46, but when they hooked up the displayport tester at the genius bar, it showed a manufacturing date of week 25. This may be the actual date of the display port and thus logic board manufacture, which is months before the machines were built, so take that as you wish; probably one of the earliest unibodies with the crap leftover NVIDIA garbage.