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CPU usage (Process “kernel_task”) is 500-600% when using constant RPM (3000 RPM).

The reason why I'm using constant RPM is I'm running 2 Thunderbolt monitors with a 15 inch Macbook Pro Retina (OSX Mavericks) and the constant "hairdryer" noise is irritating. I don't mind running the system hotter so long as the noise goes away.

Is there any solution to the high CPU usage with constant RPM around 3000?

Here are the tech specs:

Macs Fan Control 1.1.6, MacBookPro10,1, Mac OS X Unknown

Fans:
Left side-min{2151}curr{2154}max{5917}mode{1,3083}
Right side-min{1992}curr{1993}max{5477}mode{1,3019}


TempSensors:
TB0T (Bottom Enclosure) - 37.6992
TB1T (Battery Point 1) - 37.6992
TB2T (Battery Point 2) - 34.8984
TC0E () - 84.4336
TC0F () - 85.4141
TC0P (CPU Proximity) - 62.625
TC1C (CPU Core 1) - 85
TC2C () - 80
TC3C () - 83
TC4C () - 82
TCGC () - 84
TCSA () - 85
TCTD () - 0.0078125
TCXC () - 84.9531
TG0D (GPU Diode) - 79.375
TG0P () - 73.125
TG1D () - 81
TG1F () - 80.4102
TG1d () - 75
TH0A () - 41.875
TH0B () - 44.125
TH0V () - 47.1875
TH0a () - 41.875
TH0b () - 44.125
TH0c () - -1
TH0x () - 44.125
TM0P () - 59
TM0S (DIMM Module 1) - 58.5469
TMBS () - 58
TP0P () - 59.875
TPCD () - 71
TS0D () - -1
TS0P () - -1
TS1D () - -1
TS1P () - -1
TW0P (Airport Card) - 51.5
Ta0P () - 51.375
TaSP () - 46.7109
Th1H () - 52.875
Th2H () - 69.375
Ts0P (Left Palm Rest) - 35.875
Ts0S () - 45.9453
Ts1S () - 48.9961

Hello,

Actually kernel_task is a system kernel, MFC has nothing common with it. I mean that this is the first report of such an issue.

Can you please post a screenshot of kernel_task eating CPU and Macs Fan Control window as well?

Hi stevejb1,

this sounds like OS X trying to protect you from frying your MacBook.
The kernel_task will start eating up CPU cycles (and doing nothing with them) to get the processor to cool down when nothing else helps. When no other program can use the CPU, it will cool down a little.
Try setting the constant RPM higher (like 6000rpm) and see if kernel_task still uses all CPU.
If that is the case, have you tried resetting your PRAM?

cheers

After much stuffing around, I think the best solution will be to get the new Mac Pro. It appears that this sort of graphic workload is too much for a laptop to handle quietly.