Supermicro’s basic firmware GUI contains an Overclocking button. But the real excitement starts after engaging Expert mode (to reveal additional settings).
The CPU overclocking menu begins with several overclocking profiles, including 4.6 GHz at 1.30 V. That sounds like a nice limit for long-term use, and it’s even stable. CPU-Z reports a 1.298 V result and, strangely, this relatively high voltage pushed our CPU to only 92° C. That’s a full 6° lower than we expected from the lab's Core i7-4790K at that voltage, given our specific heat sink and fan.
We eventually found a 1.28 V core reading at the C7Z97-OCE’s 1285 mV setting.
Intel XMP mode pushed a pair of our modules to its rated DDR3-2800, but we needed to drop to DDR3-2666 to keep the system stable with four DIMMs installed. Perhaps a little extra voltage might have helped, but our meter insisted that the C7Z97-OCE’s 1.60 V setting yielded 1.65 volts.
Primary and secondary timings are available, and adjusting them from baseline should be easy for anyone with adequate short-term memory to remember what the box said before modification. Dropping from DDR3-2800 to -2666 without re-entering XMP timings was as easy as setting XMP mode first, before switching to manual mode to change the memory multiplier.
Though some documentation showed that the OC3 button should provide customized settings, each field was factory-programmed and re-configurable in firmware. As for the “Home” button, it’s able to keep any settings that were assigned to the base configuration (not assigned to an overclocking profile).