There are a few ways to overlock the Z97 MPower. The easiest way would be to enable OC Genie. This can be done by powering off your system and pressing the OC Genie button towards the bottom of the board then powering your system on. Doing this it brought our Core i7-4790K from 4.0 GHz up to 4.1 GHz.
Of course we knew we could do better than that and went into the BIOS and did some tweaking. While I was able to get the system to boot at both 4.7 GHz and 4.8 GHz, temperature constraints made me keep the system at 4.6 GHz for our stable max overclock.
If we compare that to the other motherboards we have tested with this processor you can see that it is on par with the ASUS Z97-A as far as overclocking potentional.