Ok so my R9 270x PCS+ idles around 35c-40c, on games like FIFA14 it hits 65c, however for taxing new age games like FIFA15 or Grid2 it goes all the way up to 90c. if I put the fan on 100% then between 80c to 85c.
I run on 1440p hence the extra juice required.
Intake/Exhaust fans on the cabinet...