VRM Overview

The VRMs have the CPU power via 16 90 A phases, SOC power from two 90 A phases and the MISC power also by two phases rated at 80 A. The cooling here is entirely passive with two large silver heatsinks, however, much of the vertical array next to the I/O panel is covered by a plastic shroud and the RGB lighting, potentially limiting surface area with case airflow. The heatsinks are also not connected via a heatpipe, which can help to even out temperatures between the heatsinks and prevent one from being saturated. The VRMs peaked at 59°C according to ASUS' software after our 10-minute stress test, while our new quad channel data logger saw a peak of 53°C on the rear of the board, with 230 W being reported as the draw over the EPS12V connector using our power meter.


Looking a little closer, the two heatsinks make thermal contact with both chokes and MOSFETs and the bulk of the heatsinks is exposed despite the large cover on the I/O shroud. The primary heatsink embedded in the I/O shroud has the RGB lighting inside and sits on top of a smaller heatsink that cools the ASMedia ASM4242 controller, but the two aren't connected with pads or heatpipes.


The board uses 90 A MPS MPS2330 power phases at a total of 16 for the CPU and two for the SoC before switching to SiC629 80 A phases for MISC. Like most of ASUS' X870 lineup, these are teamed, which includes those on the Crosshair X870E Hero, which has higher amperage and an additional two phases.