That might tell you how highly I think of the HP heatsink/fan/motherboard control system. The max I have done is the spoof you refer to, and that is only for a single step up in the processor family max TDP, not two. For the xw8600 processors if you gather the max tdp v...
Even its HP fan works with its 6-hole plug end... you just hang the last (far left hole) off the side of the 5-pin Z420/Z620 motherboard header. That last (6th) hole is just another ground jumper for the 6th pin of the Z440/Z640 motherboard header. Fits perfect am...