You might want to check also if you are running your GPU from 2 separate rails as well.
Like I stated previously, I have a 1600W ATX and I still had problems with the gtx 970 running both of the power connectors off of one rail (cord coming from my PSU) after I changed it, I havent had problems since.
Thanks for your advice. But I've been running this PC for almost 2 months without problems, also playing some Star Citizen for hours, which I think is the most taxing program on my computer, and never had this problem. It only started occurring since I installed The Witcher 3 and the newest NVidia game ready drivers. And as I said, the graphics driver even crashed a couple of times while I'm on the desktop, browsing the web. Therefore I strongly suspect it has something to do with the drivers.
Also, unfortunately I have no idea how I would check the specs you are talking about. 8-)
The ocurrence is rare enough so far that it doesn't bother me a lot. I just hope it will go away at some point, hopefully with the next driver version.
It is possible it is the drivers. The thing that leads me to believe you may have the same problem as me was crashing on the desktop. Like I said I could play Arma II at max settings for hours, but the second my crew and I got into a chopper and started flying, the game would crash with a GPU related error. I tried for about a week to figure out the problem and I couldnt for the life of me.
So one day I was browsing with chrome, pc had been on about 8 hours, and while playing a video, it crashed again.
I was getting pissed because I just spent $400 on this card and I couldnt even use it.
But then took my entire computer apart and realized I was running multiple things off of one rail including the GPU.
After I switched up the configuration, I never had a crash again. If it were drivers I would assume I would have the same problem as you guys. However, I havent had witcher 3 crash once since release, and I am playing on max settings (hairworks off) and get 70 to 80 fps constantly.
If all else fails it wont hurt to try to switch up and balance the power usage of your peripherals (dvd rom, HDD, etc) it may help a great deal because the power spikes with this card can be fairly insane.
Also (if you own a gtx 970) sign up for the class action lawsuit. Once this goes through, you may be able to get a refund or an upgrade depending on what Nvidia decides. We need as many signatures on the petition because of the whole false advertising of the 970's specs, plus free stuff doesnt hurt!!