I have a rig with 8 gig AMD RX 580 and decided to try out Nicehash on it. After a couple hours of benchmarking it started mining and the cards are only getting 295 to 300 h/s each. Why is this so low? Less than 1/2 the h/s when mining other coins...

Also looks like the card temps are getting really hot... 82*C but my fan speeds are only running at 40%??   And if I try to change any settings in the miner program that effect the GPU's the whole system freezes up.  Running AMD blockchain drivers