First, forgive me for my English.
I do not know if someone has managed to solve it or has found a way to work more stable.
After a year of patience, I found a way to make it work very stable.
the way I've done it is by installing msi afterburner and another program: clockblocker.
I do not know exactly if what I have done is good for the gpu but for now, browsing, on YouTube, and playing, the black screen has not appeared.
basically it blocks the gpu clocks since it has been reported in forums that are unstable in certain cases.
you can see my current configuration and the time it has been on my pc.
I do not know to what extent this influences the gpu, if someone has an idea please respond.
I do not take care of the damages that this may cause
do it under your responsibility.
I find it absurd that it is the user who has to find a solution since this is AMD failure.
MB: Gigabyte x99 g1 wifi
CPU: Intel core i7 5820k
GPU: sapphire r9 390 8gb nitro
RAM: 16gb ddr4 2400
link to clockblocker ClockBlocker Download Version 1.2-6.5
EDIT: after having tested I have detected that with this configuration the core clock is blocked at 300 mhz
so I've removed msi afterburner for possible compatibility problems and upload photo of my current clockblocker