As an experiment I ran the ATI Tool from http://www.techpowerup.com/atitool/ and I was quite alarmed to learn that after only around 2 minutes my GPU temperature would hover around the 70c mark When I overclocked it (slightly), the GPU temperature went up to 75c even though I suffered no lock-ups or BSOD's. Are GPU's designed to run hotter than CPU's then? I searched the web for info on my R420 GPU but although I could quite easily get technical data on number of pixel pipelines, core and memory speeds, etc. I could find nothing on maximum core temperature! When I am not doing any graphic intensive work like playing games or running the 3DMark 05 benchmark, the GPU temperature drops down to around 43c and stays there. I had no idea that my GPU temperature was that high as before I tried out the ATI Tool, I had no way of knowing what my GPU temperature actually was. Am I worrying about nothing or should I, in fact, be concerned?