50c is pretty high for idle temps on a non-reference cooler like that has..Have you taken the heatsink off and re-applied thermal paste?
You might have got a "Monday" card that had the paste globbed on without care and thus it isnt transferring heat effectively.
84c isnt so bad for load temps though,your card should be fine up to ~90c but it will start throttling and perform badly.
Regardless,you should apply new thermal paste and if the temps still are high,set a
Custom Fan Speed Curve or get ready to RMA,because it should not idle that hot unless your ambient room temps are high aswell.