Asus’ P8Z77-V LK motherboard includes an Auto OC feature. After selecting the Auto OC option and rebooting, the motherboard had tweaked our system’s configuration.
A CPU overclock to 4223MHz was achieved by way of a 103MHz base clock and 41x multiplier. A slight increase in CPU voltage was also applied. Our memory was reduced to the 18.66x divider which, with the 103MHz base clock, resulted in a frequency of 1921MHz. Timings were not adjusted.
This is a quick and easy method for users that aren’t confident overclockers to achieve a noticeable performance boost. We were impressed by the motherboard’s configured CPU settings, but slightly disappointed by the drop to an 18.66x memory divider; the 20x divider would have still presented a sub-stock, and hence stable, frequency for our 2133MHz Patriot memory.
The automatic overclock validation can be found here.
Pleased but not satisfied by the Auto OC configuration, we went in search for a higher CPU overclock.
The P8Z77-V LK motherboard’s helpful Digi+ Power Control settings allowed us to enhance our overclocking capabilities. We set the CPU Power Phase Control to Extreme and CPU Current Capability to the maximum – 120%. Both the CPU Fixed Frequency and CPU Power Duty Control remained untouched. Our CPU Load-line Calibration was initially set to Regular, but we later changed this to Very High to provide a closer match to our set CPU voltage during load conditions.
Power saving settings were disabled.
We applied a static voltage of 1.300V to allow the P8Z77-V LK to push our i5 3570K chip, while still operating within safe limits for daily usage. For 24/7 overclocks, we would recommend tailoring the Offset voltage to a setting which provides a stable frequency, allowing the motherboard to only increase the CPU’s voltage when the additional power is required.
Our maximum stable overclock was 4.7GHz, achieved via a 47x multiplier and 100MHz base clock. We tried to push for 4.8GHz, but this frequency wouldn’t even boot with our specific settings.
4.7GHz is a very strong overclock for a circa-£100 motherboard which features a 4+1+1 phase power design. It gives us an indication that the P8Z77-V LK is using efficient power delivery components which provide solid performance.
Our 4.7GHz validation can be viewed here.
While a system’s maximum memory frequency may be heavily swayed by the CPU’s individual memory controller, the motherboard’s performance can also help to obtain higher speeds.
We switched to our 2133MHz set of Team Xtreem LV memory. This kit was chosen as it is geared for overclockers, with its large heatsinks and tight timings, and we know that it is capable of frequencies in the region of 2600MHz.
Knowing that the Team Xtreem LV kit was capable of 2600MHz, we were pleased to see that the Asus P8Z77-V LK motherboard didn’t show any signs of limiting its overclocking potential. We actually managed to push all of the way up to a frequency of 2666MHz with a voltage of 1.7V and slightly relaxed timings.
For reference, using identical timings and voltage settings, our higher-priced Asus P8Z77-V motherboard ‘only’ managed to push this memory kit to 2600MHz with complete stability. This lower performance could be related to the P8Z77-V board’s older BIOS version, however.
Our 2666MHz 11-12-12-28-1T memory overclock validation can be viewed here.