I have a XFX 5850 ZNFA(Non-reference) card. My idle temp is 42 C..When I did a furmark stability test with 1280*768 res and 8x anti aliasing, the temperature of
GPU went to 88 C after about 20 mintues testing.. I did the test with the case opened. Then I played crysis for 5 min, the temperatures were around 80s.
I saw from many reviews that 5850 only goes up to 76C during loads. I had other same XFX non ref 5850 which also have temps and have some screen flickering issues so I RMA'ed it and got this one.
Then, what is your current driver version?
Already tried 10.3, 10.4, 10.8 even 10.9?
Sometime, you must try each driver until you find which version that suit you. Of course use Driver Sweeper between uninstall and installing the new one...
Well, i heard from another user on threads on the past that different driver can affect different result of card performance...
Anyway, that temps are still considered as normal, start worrying when it hit 90'C+.
I have 2 Asus 5850 Direct CU cards (non-reference cooler). One has 2 monitors connected and the other has none. The card with the monitors attached runs 45 idle and 67 load. The card with no monitors runs 35 idle and 67 max.
Screen flicker is usually only associated with drivers 10.4 and earlier when 2 monitors are connected due to the lower core/mem clocks during idle. Moving them to 400/1000 via a profile usually fixes that.