Sometimes I can't help myself.
The MacBook Pro I repaired above is now my current work machine. I've become rather fond of it I must admit. I was looking through some of the spares boxes last week and came across a gem I wasn't aware I had.
An Apple 820-2249-A Rev.2 Logic Board with nVidia GeForce 8600M GT G84-603-A2 GPU.
Lost? These revised boards were released to correct the 8600M GT issue that caused widespread failures in the MacBook Pro 2007-2008 models. They use a later revision of the G84 graphics processor that supposedly had better solder bumps compared to earlier revisions. These boards aren't that common, so this was a nice find.
With the machine apart I started looking for other components that could use attention. When I separated the heatsink from the old board I noticed the contact points were pitted and scuffed. So out came the 300, 1000 and 2000 grit to wet sand and lap the heatsink contacts. Once they were mostly reflective, I hit them with an abrasive final polishing compound. Some scratches are visible from the sanding process, but the finish is much smoother and consistent than before. Thermal compound takes care of the rest. I chose Arctic Silver Ceramique 2 for this build as it transfers heat well and holds its stability over time.
Still, I needed more airflow. I disassembled the fans and sanded out some of the casting lines and edges that could act as flow restrictions. Compare the metal texture before and after.
I've been working on this machine for three evenings now, but it's almost done. Thinking about installing OS X Yosemite on there to see how it runs, but I'll aim for a balance of software support and performance and work from there.