We performed our power consumption measurements using the same Extech Power Analyzer 380803. This device is connected before the PSU and measures the power draw of the entire system (without the monitor), including the power loss that occurs in the PSU itself. In the idle mode we start the system up and wait until it stops accessing the hard disk. The power consumption in case of single-threaded CPU load is measured while running the Pi-digits performance test, and in case of multi-threaded load – while running the Fritz Chess Benchmark test. We also used Hitman Absolution game to create complex load. The results on the diagrams are sorted out in ascending order and the results of Asus P8Z77-V LK are highlighted with darker color for your convenience.
The flagship mainboards from ASRock and ASUS feature an additional PCI Express switch, so their power consumption is higher than average. It is especially conspicuous in comparison with the much lower power draw of the ASUS P8Z77-V LK which is comparable to that of the MSI mainboard. We must also note that not all of power-saving technologies are enabled on the P8Z77-V LK by default. You can reduce its idle power consumption further by manually changing the value of each power-related option from Auto to Enabled in its BIOS. For more savings, not only in idle mode but also at high loads, you can enable EPU Power Saving Mode in the BIOS or with the onboard switch.
Now let’s see how these numbers change when we overclock the CPU and memory.
The overall picture doesn’t change. The two special products need much more power than the regular ones. The latter are comparable in their power consumption among themselves.