We measure system-wide power draw from the wall while the card is sat idling at the Windows 10 desktop for 30 minutes. A reading under load comes from running the 3DMark Fire Strike Ultra stress test 20 times.
Total graphics power for the Evoke OC is rated the same as the reference card, but in practice we saw it draw almost 15W more, likely due to the higher operating frequencies and the dual axial fans.