Don't use Furmark and stop suggesting people use it. It serves 0 purpose and most cards will cripple themselves to a lower P state if it detects it's running. Just run a benchmark if you want to test things out.
: Where did you put the temp probe on? You said the "VRM" but the VRM consists of chokes/coils/inductors/capacitors/MOSFETs/voltage regulators and not all of them really put out that much heat or need a heatsink. The only one that should have one are the mosfets.