ASRock Rack B550D4-4L Motherboard Review: B550 Goes Professional with BMC

Board Features

The ASRock Rack B550D4-4L is a professional-focused ATX motherboard which is using AMD's desktop B550 chipset. It includes support for AMD Ryzen 5000 series processors, Ryzen 4000 G-series processors with Radeon Graphics, AMD Ryzen Pro 4000 and 3000 series processors, and AMD Ryzen 3000 desktop series processors.

The B550D4-4L includes one full-length PCIe 4.0 x16 slot, with a half-length PCIe 4.0 x4 slot, with support for PCIe 4.0 coming directly from the processor. For storage, there's a single PCIe 3.0 x4/SATA M.2 slot, with six SATA ports in total. Four of these are powered by the chipset and as such, include support for RAID 0, 1, and 10 arrays, while the other two are powered by an ASMedia ASM1061 SATA controller. In regards to memory support, the B550D4-4L has four memory slots, which are capable of supporting both ECC (CPU dependent) and non-ECC memory with speeds of up to DDR4-3200 and a total capacity of up to 128 GB.

The board includes an ASPEED AST2500 BMC controller, with network access provided by a Realtek RTL8211E Gigabit port, as well as physical access via a single D-Sub video output. Other connectivity on the rear panel includes two USB 3.2 G2 Type-A, two USB 3.2 G1 Type-A ports, a Serial port, and one HDMI 1.4 video output. The B550D4-4L has an impressive network array with five Ethernet ports in total, four of these being controlled by separate Intel i210 Gigabit controllers, with support for teaming, as well as a dedicated IPMI port powered by a Realtek RTL8211E Gigabit contriller.

Test Bed

As per our testing policy, we take a high-end CPU suitable for the motherboard released during the socket’s initial launch and equip the system with a suitable amount of memory running at the processor maximum supported frequency. This is also typically run at JEDEC subtimings where possible. It is noted that some users are not keen on this policy, stating that sometimes the maximum supported frequency is quite low, or faster memory is available at a similar price, or that the JEDEC speeds can be prohibitive for performance. While these comments make sense, ultimately very few users apply memory profiles (either XMP or other) as they require interaction with the BIOS. Most users will fall back on JEDEC supported speeds - this includes home users and industry who might want to shave off a cent or two from the cost or stay within the margins set by the manufacturer. Where possible, we will extend out testing to include faster memory modules either at the same time as the review or a later date.

Readers of our motherboard review section will have noted the trend in modern motherboards to implement a form of MultiCore Enhancement / Acceleration / Turbo (read our report here) on their motherboards. This does several things, including better benchmark results at stock settings (not entirely needed if overclocking is an end-user goal) at the expense of heat and temperature. It also gives, in essence, an automatic overclock which may be against what the user wants. Our testing methodology is ‘out-of-the-box’, with the latest public BIOS installed and XMP enabled, and thus subject to the whims of this feature. It is ultimately up to the motherboard manufacturer to take this risk – and manufacturers taking risks in the setup is something they do on every product (think C-state settings, USB priority, DPC Latency / monitoring priority, overriding memory sub-timings at JEDEC). Processor speed change is part of that risk, and ultimately if no overclocking is planned, some motherboards will affect how fast that shiny new processor goes and can be an important factor in the system build.

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