ASROCK B450M-HDV R4.0 Manual page 14

Ryzen Series CPUs (Summit Ridge):
UDIMM Memory Slot
A1
-
SR
-
DR
SR
DR
Ryzen Series CPUs (Raven Ridge):
UDIMM Memory Slot
A1
-
SR
-
DR
SR
DR
SR: Single rank DIMM, 1Rx4 or 1Rx8 on DIMM module label
DR: Dual rank DIMM, 2Rx4 or 2Rx8 on DIMM module label
12
Frequency
(Mhz)
B1
SR 2667
- 2667
DR 2667
- 2667
SR 2667
DR 2667
Frequency
(Mhz)
B1
SR 2933
- 2933
DR 2667
- 2667
SR 2667
DR 2400