I am overclocking my r9 290 vapor x 4gb and i did the usual , i ran heaven and played with voltages and clocks and i got it at +13mv , +0% PL , 1080core and 1500memory , and i set up Fan curve.if i pushed it further i would get artifacts so i left it as it is then i turned off heaven and screen went suddenly black , and it does everytime i set that profile while not running heaven , when i do run heaven it works just fine underload no artifact and temperature doesnt go above 80°C. I know that i should try to increase voltage but i dont want to and it doesnt make any sense why would it crash on idle when it is totally fine under full load. Does anyone have some knowledge or experience with this kind of problem?