Power Consumption and Temperatures

For temperature measurement, I use a Reed SD-947 4 channel Data Logging Thermometer paired with four Omega Engineering SA1 Self Adhesive Thermocouple probes. One probe directly touches the chipset, and two are placed on select power stages. The last probe actively logs the ambient temperature.


For the Gigabyte B550 AORUS Pro, one probe is centered along each bank of power stages. A probe is left out to log the ambient temperature. All temperatures are presented as Delta-T normalized to 20 °C, which is the measured temperature minus the ambient temperature plus 20 °C. The end result accounts for variation in ambient temperature, including changes over the course of a test, while presenting the data as if the ambient were a steady 20 °C for easy presentation. Additionally, there is no longer any direct airflow over the VRM with this new setup, placing extra strain on the VRM cooling.

For the numbers seen in the chart above, I am now using Prime95's Small FFT test for power consumption. For temperatures, I am using the maximum temperatures recorded over the course of my standard benchmark suite (almost always during either wPrime or Blender tests). However, relatively short tests do not put enough strain on the system to get a look at how the VRM performs at the limit, so I added an additional test to try to thermally abuse Vcore as much as possible.

This test typically involves a 30 minute Prime95 run at the maximum overclock the motherboard can maintain, again with no airflow over the VRM. For B550, I chose 4.2 GHz at 1.35 V as the most intensive load I could manage in long tests without thermal throttling the CPU. Temperatures are logged every second, and the two probes are then averaged for a cleaner presentation before subtracting the ambient to calculate the Delta-T. The results are charted below.


The Gigabyte B550 AORUS Pro did extremely well in my VRM torture test, staying under 60 °C. This may seem odd considering the Gigabyte B550 AORUS Pro was by far the hottest board in my stock testing.

This is due to the finned heat-sink design Gigabyte is using. The significant reduction in thermal mass means the heatsink saturates much more quickly than other solutions. However, when subjected to an extended load, the higher surface area of the Gigabyte B550 AORUS Pro's heatsink dissipates heat more efficiently than the competition.