Chosen Solution

Yo, experts, I have 2 machines of the 2009 A1297 series. I ran ASD on both, and both show “Failed” due to Thermal Interface TIM test (test4) . It says “ Check heatsink is properly attached, using product specific theta dh+75% guardband” . That is quite a mouth-full! Moving past the lingo, I am thinking of replacing the thermal paste, but not sure if I can use one or either of the two products I have on hand: namely 1) Arctic MX-2 or/and 2) K5-pro . Also one of the machines had 2 more errors:

  1. ERROR 72- Fill rect Video 2D acceleration failed
  2. ERROR28 Mux switch failed…did not switch error Video controller internal Gmux to EG and verify (test 41) Can you please let me in on what is the best paste and how to remedy the other two exquisite inconveniences? BTW, both machine behave just fine, aside from turning into heating elements after 30 minutes of videos….but that should stop, I do not want to contribute to global warming. Update (12/18/2018) Thank you all for your input on the heat issue Can anyone shed some light on these other 2 errors shown in the ASD of one of the machines:
  3. ERROR 72- Fill rect Video 2D acceleration failed
  4. ERROR28 Mux switch failed…did not switch error Video controller internal Gmux to EG and verify (test 41) Besides the overheating, which I now fixed thanks to your help, with a non leaking heat pipe and new thermal paste, it also had shown these two errors, which I did not address yet. The only thing that is noticeably odd still with that machine is the very weird startup chime, sounding like a croak of a Blue heron on life support.

Evading your question about thermal paste, look at the logic board in the area where the heat sink ends are crimped. You are looking for a small oily type of stain where the heat sinks may have leaked and become ineffective. MacBook Pro 17" Unibody (Early-Mid 2009) Heat Sink MacBook Pro 17" Unibody Heat Sink Replacement

If you want a good quality thermal paste use arctic silver, you should be able to pick it up for under 10… I wouldn’t worry about getting the most expensive version the basic one is more than you should need. The reason it works so well is the silver content, it helps transfer the heat at a higher rate. If your a little nervous and you want to go all out, thermal grizzly it’s a liquid metal… Anything that I take apart with a CPU that’s a couple of years old I’ll usually refresh the thermal paste anyways, and with the old iMacs I hit the gpu as well…. I didn’t notice you already have the upgraded version of arctic silver… Good luck with your repair.