While it wasn't as apparent in our ASRock B450 Gaming ITX/ac and B450 Gaming K4 motherboard reviews, the newer B450 chipset has an idle power draw of only 2 W which really shows in the testing of the B450 Tomahawk. These boards are all under the same conditions, and thus the differences between them should be easy to spot. While this method for power measurement may not be ideal, and you feel these numbers are not representative due to the high wattage power supply being used (we use the same PSU to remain consistent over a series of reviews, and the fact that some boards on our test bed get tested with three or four high powered GPUs), the important point to take away is the relationship between the numbers. These are the real world values that consumers may expect from a typical system (minus the monitor) using this motherboard. This method of power reading allows us to compare the power management of the UEFI and the board to supply components with power under load, and includes typical PSU losses due to efficiency. This power supply has ~75% efficiency > 50W, and 90%+ efficiency at 250W, suitable for both idle and multi-GPU loading. Power consumption was tested on the system while in a single ASUS GTX 980 GPU configuration with a wall meter connected to the Thermaltake 1200W power supply.

This can come down to manufacturing process and prowess, so these are tested. The obvious pointers are power consumption, but also the ability for the manufacturer to optimize USB speed, audio quality (based on audio codec), POST time and latency. On the face of it, they should all perform the same and differ only in the functionality they provide - however, this is not the case.

Msi b450 tomahawk fan control