Comparison of AS5 vs. MX-4 on Haswell i7-4790K

I compared Arctic Silver 5 to MX-4 between my new i7-4790K and my NH-14D. In short, I ran mprime (Linux64,Prime95,V28.5,build 2) using large FFTs with 8 threads and logged the temps throughout the run once per second using a shell script. Ambient temp which is very important to consider did not vary more than 2 F since the system was placed in my basement where it is very consistent. The digital thermometer showed 59F as the low and 61F as the high which is approx 1 C.

Run 1 was Arctic Silver 5 which had cured for approx 52 hours. I ran mprime as noted above for 4 hours.
Run 2 was with MX-4. I ran mprime as noted above for approx 1-1/2 hours.

Histograms in blue show the temperature distributions for AS5 and those in pink show the same for MX-4. The solid black line for each core is the average temp for each core. You can clearly see differences between the two of 2-4 degrees (allow for +/-1 C due to the ambient temp range). AS5 was the superior TIM in the test experiment.
http://s19.postimg.org/st0aaae0j/histogram.png

Link to the raw data.

Test system
Processor: i7-4790K @ 4.40 GHz (vcore 1.232 volts under load)
HSF: NH-14D with 120mm and 80mm fan running at max
Motherboard: MSI Z97 MPOWER MAX AC