Exact settings I Used and Overwatch crashed as soon as i joined a game. As i said orignially, ive tried a different card(an old sapphire r7 r70) and i get the same exact message, I don't think this is related to power consuptions of the card
If there is crashing though you make core power to -30%, your PSU probably doesn't have a problem.
Test the GPU for 15 minutes with Furmark (800x600 without AA and with 8x AA). What is the maximum temperature? Does Furmark test cause a crash? Reset WattMan with OverdriveNTool software and try these. Use your Testing profile if it crashes.
Ran 2 test, one with AA off and one with AAx8, Not a single crash, but i got a crash during the 30 minutes between both(i was surfing the web) temp got to 79 max during both tests!
Try this driver. Also with WattMan, set 1411Mhz to 1340 (standard). This driver is more stable. And I think you won't have problems with standard value (1340 not 1411) and this driver. Despite all these things, if the result is the same, there is a different problem. I can't decide what the problem is and I can't help you.