Quote from: grimmi on February 09, 2017, 08:52:01 AM

That is quite high - is it in a case?

yes i a case with 2 case fans,i am using the powercolor rx480 with 1 GPU fan
http://www.powercolor.com/de/products_features.asp?id=622

if a have only one card in the system heat is at 74°C with 40% fan speed

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Just bump up the fan speeds. Go to like 70-80% and stay there. Looks like you are in some hot area. Currently with my RX 470 (Nitro+) I mine and temperatures are about 54°C at 28% fan speed with 4 other cards. But my, well if you can call it a case, is open rig have good ventilation.