Dell 5420, 7420 100

100 | Removing the System Board

Procedure

NOTE: Your computer’s Service Tag is stored in the system board. You must enter

the Service Tag in the BIOS after you replace the system-board assembly.

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 assembly.

1Disconnect the power-adapter port cable from the system-board connector.

2Remove the screws that secure the system-board assembly to the computer base.

1 system-board assembly 2 power-adapter port cable

3screws (2)

book.book Page 100 Wednesday, April 11, 2012 4:13 PM

Contents

Main Notes, Cautions, and Warnings ____________________ Contents 11 Removing the Memory Module(s). . . . . . . . . . 30 12 Replacing the Memory Module(s) . . . . . . . . . . 32 13 Removing the Hard Drive . . . . . . . . . . . . . . . . 34 14 Replacing the Hard Drive . . . . . . . . . . . . . . . . 38 15 Removing the Optical Drive . . . . . . . . . . . . . 40 21 Removing the Power-Adapter Port . . . . . . . . 54 22 Replacing the Power-Adapter Port . . . . . . . . 56 23 Removing the Coin-Cell Battery. . . . . . . . . . . 58 24 Replacing the Coin-Cell Battery. . . . . . . . . . . 60 25 Removing the Fan . . . . . . . . . . . . . . . . . . . . . . 62 31 Removing the Display Bezel . . . . . . . . . . . . . . 76 32 Replacing the Display Bezel . . . . . . . . . . . . . . 78 33 Removing the Display Panel . . . . . . . . . . . . . 80 34 Replacing the Display Panel . . . . . . . . . . . . . . 82 35 Removing the Display Hinges . . . . . . . . . . . . . 84 41 Removing the System Board . . . . . . . . . . . . . . 98 42 Replacing the System Board . . . . . . . . . . . . . 102 45 Flashing the BIOS . . . . . . . . . . . . . . . . . . . . . . 108 43 Removing the Processor Heat-Sink . . . . . . . 104 44 Replacing the Processor Heat-Sink . . . . . . . 106 Page 1 Turn Off Your Computer and Connected Devices Safety Instructions 10 Recommended Tools 2 Page 3 Page 4 Page 5 Page 6 Page 7 22 Page Page 8 Page 9 Page 10 Page 11 Page 12 34 13 36 Page Page 14 Page 15 42 16 Page 17 46 Page Page 18 Page 19 52 20 Page 21 Page 22 Page 23 60 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page Page Page 30 Page 31 Page 32 Page 33 82 34 Page 35 86 36 Page 37 Page Page Page 38 Page 39 96 40 Page 41 100 Page Page 42 Page 43 106 44 Page 45