ASUS PRIME B550M-A, AMD AM4, MATX, 128GB DDR4, 4DIMM, D-SUB, DVI-D, HDMI, PCIE

Product Information

Sliding over the right and just above the PCIe slots is the third fan header, in this case a 3-pin that only offers control via voltage. Just below that is a full-length PCIe slot and two x1 size slots. The top slot is fed from the CPU and supports up to PCIe 4.0 x16. The bottom two x1 size slots’ bandwidth comes from the chipset. Across the bottom are several headers, along with vertically oriented SATA ports. Below, we’ve listed all the headers and ports from left to right. Swinging down to the bottom half of the board, on the left side we see the exposed audio bits. We’re able to see the mid-range Realtek ALC887 chip here, alongside a couple of audio capacitors. Even though the codec isn’t a premium audio solution, many users will still find this perfectly acceptable. The B550M-A Wi-Fi has four DIMM slots that are able to support up to 128GB of RAM. Asus lists speed of up to DDR4 4600(OC) when using third-gen AMD Ryzen processors and a bit higher (DDR4 4800) with a third- gen Ryzen APU. As always, your mileage may vary as it depends on the memory kit used as well as the quality of the integrated memory controller on your CPU.

Starting with the top half of the board, we’re able to get a better look at the VRM heatsink, power lead and other goodies. Starting in the top left, the B550M-A Wi-Fi uses a single 8-pin EPS to feed power to the processor. The VRM heatsink, covering the left bank only, looks large enough to mitigate some of the heat, but I do wonder why the top bank doesn’t use a heatsink, too. As you’ll see a bit later on in testing, the VRMs were hot all around and could use some help.