I can confirm that after reverting 0e576acbc1d9600cf2d9b4a141a2554639959d50, 4.0-rc4 works correctly on my system. I've had my system running for ~20 minutes now without any hiccups. I can't say I understand what that patch does or why it causes problems on my configuration in particular, but I'd be happy to help isolate it further.
I can confirm that after reverting 0e576acbc1d9600 cf2d9b4a141a255 4639959d50, 4.0-rc4 works correctly on my system. I've had my system running for ~20 minutes now without any hiccups. I can't say I understand what that patch does or why it causes problems on my configuration in particular, but I'd be happy to help isolate it further.