Prior to testing, Intel SpeedStep and halt states were disabled in the BIOS. The CPU fan control was set to “Turbo” which allows the fan to run at a maximum speed of 1600 RPM. Temperatures were measured by Lavalys Everest. Idle temperatures were measured after the rig sat idle for 30 minutes.
CPU load was accomplished by running the latest version of Prime95, Large FFTs, for 30 minutes. The latest version of Prime95 is perfect for this task. Rather than having to run multiple instances of the program like you did in the past, the new version runs multiple instances of itself, one per thread. It runs eight instances of itself for the i7.
Ambient room temperature was 72F for all testing.
For comparison I used the Cooler Master Hyper 212 Plus. It happened to be the cooler I was using prior to the Mega Shadow. It is an economy-priced cooler that actually does an excellent job of cooling the i7 870. First I measured temperatures at stock clock.
The Mega Shadow was 7C warmer than the Hyper 212 Plus, but you really can't tell much from stock clock. The real test comes from overclocking the CPU.
I overclocked the i7 870 to 3.8gHz, not the max overclock, but a pretty healthy one, just shy of 40%. I raised the Vcore to 1.4v which heated things up a bit.