Hello -
I had this issue with my MBPro 17, along with a Client and his MBPro 15.
The solutions for our now-working MBPros include:
1. Removing the internal optical drive. Our external units provide better performance without the heat buildup.
2. Replacing the internal hard drive with a fully solid state drive. Heat buildup greatly reduced.
3. Reflowed the main board solder to a very specific set of criteria, precautions, and considerations.
4. Removed the "mesh cloth" covering the top deck grille on the underside. Airflow improved.
5. Use Cooler Master NotePal U3 Laptop cooling pads with 3 moveable 80mm cooling fans, bought from Amazon for around 35$US. These pads are a solid aluminum grille, with totally easily adjustable fans powered via USB.
6. Purchased (10$US), installed, and use Marcel Bresnik's Hardware Monitor - MacUpdate.com was our source for this. Temperature Monitor is the temperature-only variant that is still free. Be aware that this software is not meant for 2013 or newer systems.
7. I now use a new metric for temperature management - keep it below 150 degrees fahrenheit – certainly. Working temperatures for me are around 95-110 degrees, without the cooling pad - your results may vary. I'm still tinkering.
During our forensic process (we're mechatronics' types), we encountered opportunities for applying better thermal paste (wasn't much used in manufacturing?) using Arctic Silver 5 cleaner, purifier, and paste. Read and follow the directions for whomever is doing the task.
We also noticed a lot of dust had seeped into the case during use beforehand - using the optical drive was considered a primary culprit.
Our template for our chosen process was inspired by my Alienware Aurora 17 gaming laptop, festooned with so much ventilation for its dual nVidia cards.
I'm considering programming a custom pattern to lathe out of the MBPro case for additional airflow, and using a better quality mesh when done. I think our logo cut as our grille would be kewl . . . .
In one MBPro, the optical drive space is empty. This is for the video producer, and we're considering adding an additional fan with case openings in that now vacant space.
In the other MBPro, the optical drive space is occupied by the solid state drive (Otherworld Computing OWC Mercury EXTREME Pro 6G) running Mac OS X Lion with a Boot-Camped Windows 7 Ultimate backed up with WinClonePro 4. This leaves the regular hard drive bay for regular platter hard drives usually running at 7200rpm, which we manually spool down when not needed, improving heat and power management. The hard drive bay can take whatever modular loadout we need, whether it'd be a native hardware-booting Kubuntu Linux or OSX 10.4 Tiger running something in Classic.
Of course, one could use another SSD or hybrid. In our case, other than the primary OS Mac/Windows production tools, platter HDs work quite well, whether for storing documents or other non-regular tasks. For instance, Kubuntu Linux is very fast without using a SSD. (I use Parallels and Fusion for testing and with tools not used often.)
When my MBPro failed, my story echoes a lot of what I've read here. For me, it happened during a critical urgent publishing project, with just the MBPro having the necessary tools for that stage at that time while we were in the process of upgrades and migrations. Thousands of dollars US lost when I had to make the call to transfer the contract to someone else.
I understand and relate to the anger and frustration.
It took months before we decided "enough" and spent the hordes of hours necessary in research and other efforts to develop our multi-piece jigsaw-seeming solution.
While the really kewlest event was seeing these MBPros come back to life, blinking on to "my date is something else" dialog boxes, we're still tinkering.
AND
We have backups, to the rule, "Three is Two, Two Is One, One is None." I personally like Four . . . .
I can't speak to what resources you all have access to.
We just didn't like the idea of, "go out and buy another one," when we felt there were more enticing options.
We were/are fortunate we could leverage our mechatronics resources and return valuable tools back to our digital workflow.
We took the attitude of iFixit, and asked, "what CAN we do?" and did it - when it's already been declared dead, there's nowhere else to go but to the Light . . . .
We took inspiration from days of yore, and Thought Different.