Does turning off cpu cores will actually save power?

My phone is using custom kernel that has cpu hotplug in it. The hotplug name is AutoSMP and it has max cpu (big & little) core that should be online option in it. Currently I'm using 3 + 3 core configuration instead 4 + 4 core. Does it has impact on power consumption? Note: big core is oc'ed to 1.79 ghz, stock is 1.58 ghz and little core I underclocked it to 1.35 ghz, stock freq is the same as big core. gpu freq is oc'ed to 1.1 ghz, I think stock freq is 845 mhz for Exynos 7870.