ASROCK IMB-1211-D User Manual page 24

M.2 Key-E Socket (M2_1):
M.2 Key-M Socket (M2_2):
* IMB-1211-D: Switch between SATA and PCIe mode.
IMB-1210-L: SATA mode only.
* M2_2 and SATA3_1 share lanes. If either one of them is in use, the other one will be
disabled.
SATA Mode: PCIe Mode:
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