System board1 4-pin CPU power connector 2 Microprocessor socket3 Microprocessor fan connector 4 Memory slot (DIMM1)5 Memory slot (DIMM2) 6 6-pin power connector7 Coin-cell battery 8 ThinkCentre LED connector9 Internal speaker connector 10 M.2 solid-state drive slot11 M.2 Wi-Fi card slot 12 4-pin SATA power connector (connecting to theoptical drive and the hard disk drive)13 SATA 3.0 connector (connecting to the hard diskdrive)14 SATA 3.0 connector (connecting to the optical drive)15 Card reader connector 16 Serial (COM2) connector17 Clear CMOS 18 PCI Express x16 graphics card slot19 Cover presence switch connector (Intrusion switchconnector)20 Parallel connector21 PCI Express x1 card slot 22 PCHRemoving and installing hardwareThis section provides instructions on how to remove and install hardware for your computer. You can expandthe capabilities of your computer and maintain your computer by removing or installing hardware.Attention: Do not open your computer or attempt any repair before reading and understanding the Chapter1 “Important safety information” on page 1.54 M70c Hardware Maintenance Manual