4GHz Overclock on Intel I7 875k IMC/VTT voltage Blck vs Multiplier

akmac

Commendable
Dec 16, 2016
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0
1,540
Hopefully somebody can help clear this up for me as I am a little confused with my initial tests.
I have always been under the impression that the more you increase Blck the higher your IMC voltage will have to be, whereas just using the CPU multiplier should have the least impact on the IMC allowing for lower IMC voltage.
However, my initial test with this CPU shows just the opposite. Overclocking Blck to 160 passes initial stress tests with a IMC voltage under 1.2v. If I overclock using the multiplier only, it requires a minimum IMC of 1.25v or it crashes during stress tests. Any ideas on why this is happening?

CPU: I7 875k (1.38v for 4GHz)
MB: Asus p7p55de-pro
RAM: Adata XPG V1.0 1.5V 1600MHz 9-9-9-24