I am asking this to not only you, but EVERYBODY.
If you think that GPU failures in Mac Pro are because of thermal constraints, how the hell in your mind reversing the computer to OS X 10.9.5 completely removes any GPU failures?
Its very easy to call MP a failure, because of GPU problems. The thing is that the GPU problems are more spooky. They can be caused by software, or by Thunderbolt controller itself(Windows 10 and 7 also has problems with it...).
For me, MP 6.1 was most innovative computer I have ever seen, and the direction was good. Only thing it lacked IMO, was liquid cooling. And updates...
Okay, this is a long post, but please bear with me.
Don't get me wrong. I totally agree that the machine was
very innovative. It was the most perfect machine in that way for my studio. But a $4k production machine has got to be flawless or it's worthless: If it's down or out for repair it's of no use. I think there are underlying issues that may be contributing to premature failures. I was hoping that I would be one of the lucky ones, but it was not to be. I'm just not willing to roll the dice on another unit just to run-up the mileage on my car when I have to take it to a Genius Bar and back, again and again.
I did see a marked improvement on my (now gone) 2013 8-core D300 machine when
10.12.5 was released and I did yet another clean install of everything. It was just a little less
crashy. YMMV. I didn't have any fan issues or heat issues during the normal operation of that unit, it mostly just crash sometime overnight during sleep. It always passed the hardware test. I went through different levels of Apple Care Support. They replaced the i/o board, they replaced the graphics board (not the actual D300 cards, but the board they sit on.) Got the machine back from the service center and...... Crash! I ended up with the folks at Apple Customer Relations. They refused to replace the entire machine even though I was still covered under Apple Care.
I even checked the firmware versions of my Apple Thunderbolt cables. I never ran this machine hard and the fact that Apple was unwilling to swap out the machine was rather absurd given how expensive these machines cost. -Even now. I was tempted to pick up a 6-core, but I just can't trust a design that Apple won't stand behind, even with Apple Care. I'm fairly certain that the issues are perhaps no deeper than lead-free-solder. At least if it was like the old
capacitor plague from many years back, we'd just get new logic boards and hopefully, the lesson would have been learned. Apparently, emoji design, media-tainment subscription services and the obsession with removing useful ports making things thinner at the cost of functionality and durability is more important than real R&D improvements.
If I could be assured that whatever flaws in the design have been corrected for new builds, I'd buy one today. I just can't trust it, and that's a terrible distraction in a studio environment.
The only thing that I was assured of in dealing with Apple is that my call was important to them.
What I also learned was that my 2012 i7 2.6 GHz Mini runs perfectly with the exact same hardware and cabling attached. -And I've never had invoke warranty on a 2012 Mini. A $4k computer had better run with utter perfection. Actually, in this age of engineering, there is no excuse for things not being essentially flawless unless the design or materials are flawed. I know that there's no free lunch. -I'm looking at the tin-whiskered green-washers.