I have a Koolance AR-597 on my 5970... GPU temps are good, under 45+C with 1.25V/1ghz running Furmark, but the VRMs getting really hot... up to 130C.
With no overclocking/overvolt they get up to 75C, idling around the same as the GPUs, 35C.

I need to tear it apart and check for bad contact I think.