clcool :
Hello, just recieved a new ASUS Strix 970 Yesterday, ever since then the performance has been great but i constantly crash all the time in game then i must reboot, the screen would just turn full grey or any colour and freeze. i downgraded my Drivers now it reboots by it self, i just Ran uniengine Heaven extreme HD for 30 minutes no problems at all so strange and frustrating.
Specs
i5 4690k
Gigabyte Z97P-D3 Intel LGA1150 Z97 ATX Motherboard
8GB Ram
Hello!
I will do my best to help you with your rather frustrating issue.
Do you know the max watts of your PSU? The first thing that came to my mind, was maybe your PSU was peaking its voltage level. This would cause a crash.
If your PSU is more then capable of powering your system, then it may be a problem with the GPU its self.
I used to have an 8800GT, however signaling the end of its life, it used to crash and freeze on the last image on screen. It happened in games frequently, usually in the menus. It only crashed when playing games, but I didn't test it on benchmarks, it probably would of crashed on those as well. It sounds similar to your issue, apart from mine displayed some colour.
If it looks familiar to what I had, it is likely to be a hardware problem with your GPU. I recommend contacting the manufacturer to see if you can get an RMA or a refund. But make sure you explore the possible solutions first.
Here is the image: http://postimg.org/image/638tu4065/
What I find interesting if that you can run benchmarks fine, it is rather strange as you said.
Hope this helps!