Typically overclocking of CPUs requires increasing the voltage to reach the higher clock speeds but a number of reports on Ivy Bridge overclocking have found that increasing the voltage rapidly results in heavier power consumption and heat.
AnandTech’s report on overclocking Intel’s Ivy Bridge suggested that former owners of the previous generation Sandy Bridge processors may be "severely disappointed" by the overclocking potential of the new 22nm Ivy Bridge.
"Ultimately, Ivy Bridge hates voltage," said AnandTech’s Ian Cutress.
The Tech Report found that additional voltage wasn’t generally necessary to reach pretty decent speeds. "The Core i7-3770K was stable at 4.4-4.5GHz without so much as an extra millivolt applied to the CPU," they said.
Perhaps the most interesting feature of Ivy Bridge is the ability to run at low voltages and consume very little power, particularly as Intel has played their usual conservative hand in terms of default voltage/speeds.
To illustrate the point, AnandTech found that the Ivy Bridge flagship i7-3770K could be simultaneously overclocked from 3.5GHz to 3.9GHz while also reducing the voltage to 0.9v volts. The result is higher performance while raising the CPU temperature just 2 degrees to 53C.
The ‘undervolting’ potential of Ivy Bridge probably shouldn’t be a surprise given that Intel sells various postfix labelled versions of each processor which draw less power than the standard model.
Those demanding the best performance can still achieve something like 4.4GHz with the i7-3770K while hitting a heatsink temperature less than 70C. Not bad.
The moral of the story is, Ivy Bridge overclockers would be wise to read up before using similar settings to earlier Sandy Bridge chips.