^^^ This. PCIe 3.0 just has higher memory bandwidth as far as I know,
but in real world scenario/ gameplay it won't make much of a difference. 5% maybe.
The power delivery that I mentioned with the gigabyte motherboards are these:
UD3H has a 8 phase power design (8+2)
UD4H has a 16 phase power design (12+2+2)
Basically it means smoother power delivery to the CPU.
The UD4H also has a few more SATA ports and a better heatsink on the VRM's (voltage regulator modules)
The Maximus VI Hero has a 10 8 phase power design.
Somebody else might be able to tell you more about what it actually does.
I guess it just helps with proper power distribution and when overclocking
and in that case, I would say more is better.
Edited by JambonJovi - 11/9/13 at 12:03pm