ASRock B550M Pro4 Upgrade Guide: RAM, SSD and CPU

Lifecycle and support

A current model: sold new and supported.

Dates not listed haven't been published by the manufacturer or a reliable third party.

Memory (RAM): 4 DDR4 slots, up to 128 GB

The board has four full-size DDR4 DIMM slots running in dual channel, and the total maximum is 128 GB. It takes unbuffered modules only (ECC or non-ECC), so registered server modules are not supported. There are no SO-DIMM (laptop-size) slots and no soldered memory. XMP profiles are supported.

ASRock doesn't state a maximum size per module. Four slots and a 128 GB total would suggest 32 GB per slot, but that is our inference, not a confirmed figure, so check ASRock's memory support list (QVL) before buying 32 GB modules.

Official speeds go up to 3200 MT/s. Anything faster is an overclock and depends on your CPU: up to 4533+ with Ryzen 5000 and 3000 CPUs, and up to 4733+ with Cezanne and Renoir APUs. Picasso APUs (Ryzen 3000 G) are lower, at 3333+ (OC) and non-ECC only. ECC with APUs only works with PRO CPUs.

Buying tips

• Buy identical modules (same brand, speed, size and chip type) for dual channel; a matched kit is the easy way.
• With two modules, use slots DDR4_A2 and DDR4_B2 first.
• Treat anything above 3200 MT/s as an overclock that may need tuning.
• Check the QVL for your exact kit, especially for large modules.
• Use a 64-bit Windows; 32-bit versions can't use all the memory.

Storage: two 2280 M.2 slots and six SATA ports

M2_1 (Hyper M.2) takes an NVMe SSD in the 2280 size only. It runs at PCIe Gen4 x4 with Ryzen 5000 or 3000 CPUs, and at Gen3 x4 with Cezanne, Renoir or Picasso APUs. M2_2 is also 2280 only and takes either an M.2 SATA drive or an NVMe drive at up to Gen3 x2, so it is slower than M2_1. NVMe drives work as boot disks, but NVMe is not supported with the Athlon 3000G.

M2_2 shares lanes with SATA ports 5 and 6. If you put a drive in M2_2, those two SATA ports are disabled, and the reverse is also true. The board has six SATA3 (6 Gb/s) ports in total, with RAID 0/1/10, NCQ, AHCI and hot plug. You need SATA cables, and the 2.5-inch or 3.5-inch bays come from your PC case, not the board.

There is no 22110, 2260 or 2242 support listed, so shorter or longer M.2 drives are not an option. Don't confuse this board with the ATX B550 Pro4, which has different M.2 slots. ASRock doesn't state a maximum drive capacity. The board also supports the ASRock U.2 Kit.

Buying tips

• Buy a 2280 NVMe SSD for M2_1; a Gen4 drive only runs at Gen4 speed with a Ryzen 5000 or 3000 CPU.
• If you need all six SATA ports, leave M2_2 empty.
• Check that M.2 SATA or NVMe is what you're buying for M2_2; it takes both, at Gen3 x2 at most for NVMe.
• Make sure your case has a free 2.5-inch or 3.5-inch bay before buying a SATA drive.

CPU: AM4 socket, Ryzen 3000 to 5000

The processor is socketed (AM4, AMD B550 chipset), so it can be replaced. ASRock lists Ryzen 3000, 3000 G, 4000 G, 5000 and 5000 G series desktop processors and points to its CPU support list for details. The board is a single-socket design.

ASRock's documents disagree on the details. The older manual lists only Matisse (Ryzen 3000) and Renoir (Ryzen 4000 G), while the current product page also lists Ryzen 5000 (Vermeer), Ryzen 5000 G (Cezanne) and Ryzen 3000 G (Picasso). The newer page reflects later BIOS support, so a board running an old BIOS may not boot a newer chip. The older manual also says the board isn't compatible with Athlon processors, and the current page notes that NVMe doesn't work with the Athlon 3000G.

Your CPU choice affects other parts: memory speed limits, the PCIe speed of the main x16 slot and M2_1 (Gen4 with Ryzen 5000/3000, Gen3 with APUs). The video outputs only work with a G-series APU. ASRock doesn't give a maximum CPU wattage (TDP) for this board, so check the CPU support list for the exact chip you want. The board has an 8-phase power design.

Buying tips

• Look up your exact CPU on ASRock's CPU support list and note the minimum BIOS version it needs.
• Check your current BIOS version before buying a Ryzen 5000 or 4000 G chip.
• Buy a G-series chip only if you need the onboard video outputs; other CPUs need a graphics card.
• Plan for a suitable heatsink and fan; the manual says to fit one with thermal grease.

How to upgrade

Before you start

• Find your current BIOS version (in the BIOS setup screen) and compare it with the minimum required for any new CPU on ASRock's CPU support list.
• Back up important files before opening the PC.
• Have your owner's manual to hand for the exact slot and socket positions.
• For a CPU upgrade, have thermal grease and a suitable heatsink and fan ready.
• Check that your case has a free drive bay and you have SATA cables if you're adding a SATA drive.

Steps

1. Back up and update first
   Back up your data. If you're fitting a new CPU, check the BIOS version and the CPU support list first, and update the BIOS before swapping the chip if the list says it's needed.
2. Power off and unplug
   Shut the PC down, switch off the power supply and unplug all power cables, as the manual instructs before installing a CPU.
3. Ground yourself
   Touch bare metal on the case or wear an anti-static strap before handling components, and hold parts by their edges.
4. Open the case
   Remove the side panel so you can reach the board. See the owner's manual for the exact layout of the sockets and slots.
5. Install the part
   For RAM, fit matched modules, starting with DDR4_A2 and DDR4_B2 if you have two. For an M.2 SSD, use a 2280 drive in M2_1 or M2_2; remember M2_2 turns off SATA ports 5 and 6. For a SATA drive, mount it in a case bay and connect a SATA cable. For a CPU, follow the manual's Installing the CPU section, then refit the heatsink and fan with thermal grease.
6. Close up and reconnect
   Refit the side panel, reconnect the power cables and switch the power supply back on.
7. Check the BIOS
   Start the PC and enter the BIOS setup to confirm that the new CPU, memory size and speed, or drive is detected. If you added an XMP memory kit, enable the profile there if you want it.

Good to know

• ASRock doesn't state a maximum memory size per module; check the memory support list (QVL).
• ASRock's older manual and its current product page disagree on supported CPUs; the current page is the more up to date, but check the CPU support list for your exact chip.
• Minimum BIOS versions for each CPU aren't listed here; ASRock's CPU support list has them.
• No maximum CPU power (TDP) is given for this board, so check the CPU support list for high-end chips.
• Memory speeds above 3200 MT/s are overclocks and not guaranteed.
• No maximum drive capacity is stated, and drive bay sizes depend on your PC case.
• Don't mix this board up with the ATX B550 Pro4, which has different M.2 slots and a different Picasso memory speed.

Frequently asked questions

How much RAM can the ASRock B550M Pro4 take?

Up to 128 GB in total across four DDR4 slots, using unbuffered modules. The maximum size per module isn't stated, so check ASRock's memory support list (QVL) before buying 32 GB modules.

Does the B550M Pro4 support Ryzen 5000 CPUs?

The current ASRock product page lists Ryzen 5000 and 5000 G series, but the older manual lists only Ryzen 3000 and 4000 G. You may need a BIOS update first, so check your BIOS version against ASRock's CPU support list.

Can I use any M.2 SSD in the B550M Pro4?

No. Both M.2 slots are 2280 only, with no 2242, 2260 or 22110 support. M2_1 takes NVMe drives, while M2_2 takes M.2 SATA or NVMe drives.

Why are my SATA ports 5 and 6 not working?

They share lanes with the M2_2 slot. If a drive is installed in M2_2, SATA ports 5 and 6 are disabled.

Does the B550M Pro4 support PCIe 4.0 SSDs?

Yes, in the M2_1 slot, but only at Gen4 x4 with Ryzen 5000 or 3000 CPUs. With Cezanne, Renoir or Picasso APUs it runs at Gen3 x4. M2_2 is limited to Gen3 x2.

Does the B550M Pro4 support ECC memory?

It supports ECC and non-ECC unbuffered memory. With Picasso, Cezanne and Renoir APUs, ECC only works with PRO CPUs.

Official documents and references

• ASRock B550M Pro4 product page
  Official specifications for memory, M.2 slots and CPU support
• PDF ASRock B550M Pro4 manual (PDF)
  Installation instructions for the CPU, memory and drives
• ASRock B550M Pro4 manual on ManualsLib
  Online copy of the manual, including dual-channel memory guidance
• ASRock comparison: B550M Steel Legend vs B550M Pro4
  Side-by-side specs, including the power phase design