Dell XPS 15 (L501X, Late 2010) - Manual (Page 104)

104 System Board
9 Disconnect the USB board cable and speaker cable from the connectors on
the system board.
10 Turn the top cover over.
11 Remove the heat sink (see "Removing the Heat Sink" on page 95).
12 Remove the processor module (see "Removing the Processor Module" on
page 99).
13 Disconnect the Bluetooth cable and AC-adapter cable from the connector
on the system board.
14 Remove the five screws that secure the system board to the top cover.
1 USB board cable connector 2 speaker cable connector
1 2