Dell XPS 15 (9530, Late 2013) - Manual (Page 45)

Removing the System Board | 45
Procedure
NOTE: Your computer’s Service Tag is located under the system badge.
You must enter the Service Tag in the BIOS after you replace the system board.
NOTE: Before disconnecting the cables from the system board, note the location
of the connectors so that you can reconnect them correctly after you replace the
system board.
1 Using the pull tabs disconnect the I/O-board cable from the system board.
1 I/O-board cable 2 pull tabs (2)
1
2