I have the similar problem on Z800 and no - the cooling system does not perform as designed (unless HP have designed Z800 to run CPU at Tcase temps).
My motherboard temp. sensors read 20C lower than core temps so, core temps can go 80C and MBO sensor shows 56C.
This results in fans rpm to stay the same as definied in BIOS (idle speed) whike at 80C they should be spinning at max.
Luckily, I was able to solve my Z800 bugs by using SpeedFan utility.
Shame on you HP.. there should be HP utility to control fan speeds out of the box.
Anyway, I wish that HP uses lager fans that would be able to cool CPU and internals at much lower noise.
