me too but not is for temperatue....
i have 1x R9 280x Sapphire win 7 x64 claymore 5.3 driver 15.12 and set overclocking to 1100/1600 powelimit 20, -dcri 60 -ethi 16 i get 17.2 M'hs ETH and 517 m'hs SIA. dual miner when i dont use overclock i get 15 M'hs eth and 240 mhs sia
i test to use ethOS distribution linux and get 17mhs max..
why people can mine with 20mhs and i cant?

?
Thanks rep++
Decrease -dcri to values between 40 and 50. You can do that during mining using "+" and "-" keys to find your sweet spot of dcri value.
EDIT: edited messed quotations