Power Consumption And Temperatures
A long overdue change was made, and December’s stock $500 PC was tested as most of you would use it, with power saving features enabled. However, during overclocking, Cool’n’Quiet was disabled, the 120 mm exhaust fan raised from low to high speed settings, and the CPU fan’s target speed increased from 50% to 90%.
Loading all CPU and GPU cores with FurMark + Prime95 gives us a good look at the maximum potential power draw the system could face.
The use of a balanced power scheme and energy saving features results in much lower idle and CPU load consumption, but the switch to a more efficient power supply also must be factored into the equation.
Estimating 82% efficiency for the EarthWatts 380 W equates to a peak output draw during full CPU and GPU load of roughly 280 W for today’s overclocked system.
We used the ASRock M3A770DE’s socket sensor for the CPU, and charted peak temperatures above ambient. There’s really too much going on here to pinpoint a meaningful comparison to the prior $400 PC. The stock $500 PC has a lower VID CPU, better CPU cooler, and enabled power saving features, yet the former machine had greater chassis air flow and a higher target rotational speed on its CPU fan.
One thing is clear: the four-core overclock in September was completely limited by CPU temperature, while December’s overclock is mainly limited by the system builder’s unwillingness to pump higher voltage into the CPU.