I can run these tests looping for a day and they don't crash on their own, but together or in an intensive game, they do crash. what is the problem? MCH core? PSU? temperatures are all pretty good even at time of crash.
I had the same issue, for me it was a power issue. I believe what solved it was upping the vcore 1 notch from where it was, as the tiny drop in voltage from loading the system up was causing instability.