Hi, i recently upgraded from a very problematic Strix 970 to a Strix 980 Ti and was quite pleased by the performance, out of the box without any changes it hit a wooping 1414mhz. Started tweaking with it and arrived at max boost 1493mhz with +87v/+110% power/+50 core/+400 mem at 77 max temp/50% fans.
Everything was working perfectly until this morning when in the middle of a MWOnline game i had a sudden driver crash, followed by monitor turning off and me having to reset the pc. Power on and 1st strange thing, it wouldn't downclock from 1190mhz to its power saving states below. in every game so far it downclocks exactly 13mhz below the clock i had been running with, AFTER HITTING 63 DEGREES.

Help ?

AMD FX-8370, 4.7ghz (23.5 x 200)
CPU 1.392v - CPU/NB 1.3v - CPU/VDDA 2.5V
NB 2600mhz / HT Link 2600mhz
Noctua NH-D15 - 2x140mm stock
Asus Crosshair V Formula
ASUS Strix GeForce GTX 980 Ti - STRIX-GTX980TI-DC3OC-6GD5-GAMING
16GB Corsair Vengeance Pro CMY16GX3M2A1866C9 - 9-10-9-27 2T 1866Mhz
2x Samsung 850 EVO 250gb
EVGA SuperNOVA G2 750W Gold
Fractal Define R5 Black - 8x Fractal Design Dynamic GP-14
Acer H223HQ 21.5" Wide LCD Monitor
Windows 10 Professional 64bit