ASROCK IMB-1211-D User Manual page 27

M.2 Select (For IMB-1210-D / IMB-1210-L only)
(2-pin M2_SEL1)
(see p.14, No. 25)
* M2_2 and SATA3_1 share lanes. If either one of them is in use, the other one will be
disabled.
Open : For SATA3_1
Close : For M.2
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