I have a new HIS Radeon HD 6870 IceQ 1GB GDDR5 Graphics Card. MSI afterburner shows stock voltage at 1.23V and GPU-Z shows 0.945V. Under full load it goes up to 77 degree celsius and uses 1.23V maximum. At idle it stays at 43 degree celsius and uses 0.945V according to GPU Z.
Now if I limit voltage to 1.745V in MSI afterburner (which is supposed to be default for hd 6870) then under full load it goes up to 70 degree celsius(less than before) and uses 1.745V. But now it remains at 1.745V all the times and shows 46 degree celsius while idle, according to GPU Z.
so my problem is that, if I limit voltage then to 1.745 then it always uses this voltage and shows high temperature while idle, and if I don't limit voltage it goes 77-80 degree celsius during full load.
Another thing is that, while surfing internet it reaches 53 degree celsius and whenever I watch movie it reaches 57 degree celsius. I have aggressive fan profile, 100 % fan speed at 60 degree celsius.
I had same graphics card but that was staying 38 degree celsius while idle and 68 degree celsius under full load.
I'm pretty sure Afterburner is checking memory temps and not the GPU temp (AMD cards have 3 diodes to check temps everywhere). I tested this by cranking up the fan speed to 100% and while GPUZ / Speedfan reported lower GPU temps, Afterburner only saw an increase in temp as the memory got hotter under full utilization.