I recently noticed that my gpu rx 580 4gb starts to thermal throttle at only 70C. I have no idea why this happens and I already tried to keep my card under 70C but its impossible. I have undervolted it and put my fan speed higher to no use, I average ~75C, haven't seen it go higher than 77C. However before I knew what undervolting was I had the card at default settings and it was thermal throttling at over 80C.