Good luck.
Maybe since you have a 550 card, you can do what I did (THE only thing so far that has made my card stable, and its funny you mention the degree's celcius, because I have noticed that when I go over 155f, I get ALL kinds of issues, but 151/152f and I can play decently in games).
Here is what I HAVE to do to even play a game:
1. Install the 550 as a dedicated PhysX card.
2. Install MSI Afterburner.
3. Set afterburner to have 100% fan speed on the 900 card, AND set priority to "GPU Temp Target" (this only works when I go OVER nvidias/evga's regular temp top setting of 85C, so I set it to 86C or 87C, and it works. I have no idea what your cards top temp throttled setting is, but you should be able to ask someone here what it is, or read a review and see what it is. Afterburner is setting mine to 83c, instead of the REAL 85c, so keep that in mind also)(since both the power and temp are set together, you HAVE to slide both at the same time, or at least msi does it that way, I dont really know much about this stuff. What I DO know is that the 85c set by the mfr is BS on my card, as it reaches that temp in 1-2 minutes of even LAUNCHING a game, let alone playing it).
4. Run afterburner before you start a game.
Only THEN can I play a game w/o issue.
Sometimes it seems bad right from the start, and I have to reboot the computer and do it all over again, but I got it working in games now, so I dont care.
I KNOW its an evga/nvidia issue, everyone KNOWS there is an issue, but noone will do squate about it.
I did all that stuff too, and 6 cards later, still have issues.
But, since I have a workaround for right now, I dont care. Maybe when another game REQUIRES me to have a driver over 388.00, and I start having issues yet again, then I will comne back to it.
But, for now, try that and see if it works.
Remember, you have to SET afterburner to 86/87C AND move Priority to gpu temp, EVERY time you launch afterburner.
I highly suggest to NEVER put afterburner as 'boot with windows' also, as I have had bad experiences with that, as have others.
Good luck, you are going to need it.
:(
post edited by Dave3d - 2018/02/09 12:38:26