Power Consumption and Temperatures

Taking a look at the VRM heatsinks, ASRock is using ones that are suitable for the intended use case, which is gaming. However without any air-flow temperatures may become a problem.




For the ASRock Z790 PG Sonic Edition thermal testing, one probe is placed along each bank of power stages. A probe is left out to log the ambient temperature. For temperature measurement, a Reed SD-947 4 channel Data Logging Thermometer is used, paired with four Omega Engineering SA1 self adhesive thermal couple probes. All temperatures are presented as Delta-T, which is the recorded temperature minus the ambient temperature as a base. The end result accounts for variation in ambient temperature, including changes over the course of a test.

Tests are conducted over a 30 minute period. For testing, the Intel i7 12700K is overclocked to 5 GHz at 1.35 V to reach 300~ Watts. Next is the Intel 13900K, used in a stock configuration. Tests include two runs; one with a fan placed on the VRM heatsinks to simulate case airflow and one without. If the heatsink has a internal fan, it is not disabled for these tests.


Prime95 is great for getting maximum thermals and wattage output for VRM torture testing. However, this program isn't a realistic use-case for the average consumer. Here we see the power stages reach 100°C externally and continue to go up until the 30 minutes are up. In the past, once 100°C the test was ended, but now we let it go until it blows up or the time is up. Understand, this is only possible if you enable overclocking functionality in the BIOS.


With a power target set to (PL1=253 W) VRM temperatures are a little lower. The small dips observed in this Cinebench graph comes from a minor drop in temperature between rendering scenes. These will look very similar to if the CPU reached a throttle limit. Overall Unsurprising outcome considering how Prime95 torture test went.


Here we have the most important test for this particular motherboard. Most looking at this product tier are not planning on using the computer as a workstation. When it comes to strictly gaming, the power stages under the smaller heatsink are about 10°C higher, but still not concerning. With or without case airflow, passive cooling is fine and this motherboard should be able to keep the power stages in check for an indefinite amount of time. Of course, it is always recommended to have some amount of airflow within the computer case.