Yamaha CRW2100SX - Manual (Page 26)

Setup Procedures
17
5 Insert your SCSI card into the slot using both hands. Make sure it is seated
firmly in the slot. Then secure the card by replacing the screw used for the
blanking plate.
Replace screw
Insert SCSI card
6 Attach the outer casing of the computer and any screws that were removed.
Then reconnect the computer to the electrical outlet but do not power it up
yet.