It's just gpu that runs at 70 Celsius, both cpu are around 45 degrees.
I'm sure everything is well-configured because if I switch to catalyst temperatures are ok, gpu is around 50 and also cpu are ok.
I'm not surprised of those temps since I also get 64-65 degrees using ForceLowPowerMode in xorg.conf without KMS.
I have three acpi sensors, two for cpus and one for gpu, so I can read those temps just with acpi tools. I'm sure that it's gpu temp because reading it through aticonfig (using catalyst) returns the same value.