MSI MAG B550 TOMAHAWK
Board code MS-7C91 Motherboard, from 2020 144 hardware reports
Memory

Up to 128 GB
4 full-size slots
SSD

1+ M.2
At least 1 M.2 SSD slot
SSD length
Coming next
Checked from separate sources
Upgradable
Yes. 4 slots, up to 128 GB seen working.
It takes DDR4-3200 full-size sticks (DIMM).
- Slots
- 4 DIMM slots
- Type
- DDR4-3200 288-pin DIMM
- Most seen working
- 128 GB in two or more machines
- Firmware says
- 128 GB maximum
- SSD slots
- At least 1 M.2 SSD slot listed by the firmware
- How sure
- 144 of 144 reports show this layout
See 32 GB DDR4-3200 DIMM on AmazonOpens an Amazon search for this exact spec.
Worked out from 144 hardware reports of this motherboard. Sources and method. Updated 9 Nov 2026.
4 full-size slots
Illustration Questions
Can I upgrade the RAM in the MSI MAG B550 TOMAHAWK?
Yes. 4 slots, up to 128 GB seen working. It takes DDR4-3200 full-size sticks (DIMM).
What type of RAM does the MSI MAG B550 TOMAHAWK use?
DDR4-3200 full-size sticks (DIMM, 288-pin).
How much RAM can the MSI MAG B550 TOMAHAWK take?
Machines in the reports run up to 128 GB. That matches the 128 GB maximum the firmware reports.
Does the MSI MAG B550 TOMAHAWK have an M.2 SSD slot?
Yes. The firmware lists at least 1 M.2 SSD slot, in 144 reports. Some firmware leaves a slot out, so there may be more.
Is this my motherboard?
The model name is printed on the board, usually between the memory slots or near the CPU socket. In Windows, open System Information and look at "BaseBoard Product"; it should read MAG B550 TOMAHAWK or MS-7C91.
More MSI B550 boards
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- MAG B550M MORTAR (MS-7C94)
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- MAG B550 TOMAHAWK MAX WIFI (MS-7C91)
- MPG B550 GAMING CARBON WIFI (MS-7C90)
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- MPG B550I GAMING EDGE WIFI (MS-7C92)
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