Thats almost 7 months and yet this problem dont go away. I already used Windows 8.1, Windows 10 before and after Anniversary Update. Every heavy load 3D application NEVER caused any issue for me and i played many hours of heavy 3D game in this period. Almost every 24-48 hours i got a Black Screen of Death while browsing along time. It happens with Firefox, Chrome and Edge. Firefox and Edge occurs more frequently while with Chrome it take several days to happen. I already made 2 clean system install since Anniversary Update, i keep all browsers with hardware acceleration disabled except for Edge which has no option to enable/disable. The symptons already happeed in form of Thread stuck in device driver BSOD's and TDR, and most of times even the stuck black screen save TDR dump files 0x141 in C:\Windows\LiveKernelReports\WATCHDOG.
Two days ago when Windows10 KB~34/KB~36 updates started downloading/installing in background it caused a black Scren of Death, so after hard reset it finished the installment at startup and Windows become corrupted. So i fresh install Windows 10 again.
Before Anniversary Update, driver 15.11/15.12 were stable drivers for this issue, but after Anniversary update no more. AMD already caused too much hassle.
Asus Z87 Plus
2x 8Gb 2400mhz Trident X
R9 390 Sapphire Nitro
EVGA 750 B2
Win10 Pro x64
EDIT 1: After RMA card first time the card comeback with same problem, black screen during light tasks which keep clock/voltage fluctuating, because the warranty guys give too much attention to 3D heavy benchmarks only and made no tests in light tasks environments like i asked. For 3D heavy applications the card is fine. The card apparently has voltage degradation for 2D to 3D clocks fluctuation. The card runs fine for first 3 months, after that the card started cause black screen over light tasks.
When running a heavy 3D app the voltage of card stays at 1.175v-1.263v and keep full stable. When running light tasks and the card apply 3D clocks it apply 1.10v to 3D clocks for things like video playback what is normal because video playback is not too hungry. Then card start spiking memory clock to 150/1500mhz and voltage too keep spiking together from 0.992v-1.00v-1.10v and after long period it cause black screen or some type of crash. Decreasing the memory clock to 1250mhz stop any crash while all the rest works at same way. So there is some voltage instability from the card to light tasks and first P-states. I recorded almost all my black screen and reopened second time RMA which is not finished yet, but i hope this time they identify the problem since i give they a lot of videos demonstrations to explain the issue.
EDIT 2: So i RMA'ed the card a second time october 2016, this time with better explanation and video demonstration to the RMA guys. They confirmed than card was hardware defective and there was nothing they can do to fix it. I get a refund since they cant replace the card. So that's it, take care.