Lenovo 3980 - Manual (Page 74)

Figure 4. System board part locations
1 Battery 8 SATA connectors (2)
2 Thermal sensor connector 9 Front USB connector 2
3 Clear CMOS (Complementary Metal Oxide
Semiconductor) /Recovery jumper
10 Front audio connector
4 Serial (COM) connector 11 System fan connector
5 Front panel connector 12 Internal power distribution connector
6 Front USB connector 1 13 Microprocessor
7 Memory slots (2)
Removing the computer cover
Attention
Do not open your computer or attempt any repair before reading and understanding the “Important safety information”
in the ThinkCentre Safety and Warranty Guide that came with your computer. To obtain a copy of the ThinkCentre
Safety and Warranty Guide, go to:http://www.lenovo.com/support
This section provides instructions on how to remove the computer cover.
CAUTION:
Turn off the computer and wait three to five minutes to let the computer cool before
removing the computer cover.
To remove the computer cover, do the following:
68 Hardware Maintenance Manual