Dell Latitude 7420 Service Manual page 4

Audio board.........................................................................................................................................................................40
Removing the audio board........................................................................................................................................ 40
Installing the audio board........................................................................................................................................... 41
Speakers.............................................................................................................................................................................. 42
Removing the speakers..............................................................................................................................................42
Installing the speaker.................................................................................................................................................. 43
SmartCard reader..............................................................................................................................................................44
Removing the smart card reader............................................................................................................................. 44
Installing the smart card reader............................................................................................................................... 46
System board......................................................................................................................................................................47
Removing the system board..................................................................................................................................... 47
Installing the system board....................................................................................................................................... 49
I/O board.............................................................................................................................................................................52
Removing the I/O board............................................................................................................................................52
Installing the I/O board.............................................................................................................................................. 52
Power button with fingerprint reader.......................................................................................................................... 53
Removing the power button with fingerprint reader..........................................................................................53
Installing the power button with fingerprint reader............................................................................................54
Keyboard............................................................................................................................................................................. 55
Removing the keyboard............................................................................................................................................. 55
Installing the keyboard............................................................................................................................................... 57
Palmrest assembly............................................................................................................................................................ 59
Removing the palmrest assembly............................................................................................................................59
Installing the palmrest assembly.............................................................................................................................. 60
Chapter 3: Software.................................................................................................................... 62
Operating system.............................................................................................................................................................. 62
Drivers and downloads..................................................................................................................................................... 62
Chapter 4: BIOS setup.................................................................................................................63
BIOS overview................................................................................................................................................................... 63
Entering BIOS setup program........................................................................................................................................ 63
Navigation keys..................................................................................................................................................................63
One Time Boot menu........................................................................................................................................................64
System setup options.......................................................................................................................................................64
Updating the BIOS............................................................................................................................................................ 74
Updating the BIOS in Windows................................................................................................................................ 74
Updating the BIOS in Linux and Ubuntu................................................................................................................ 75
Updating the BIOS using the USB drive in Windows..........................................................................................75
Updating the BIOS from the F12 One-Time boot menu.....................................................................................75
System and setup password...........................................................................................................................................76
Assigning a system setup password....................................................................................................................... 76
Deleting or changing an existing system setup password................................................................................. 77
Clearing BIOS (System Setup) and System passwords...........................................................................................77
Chapter 5: Troubleshooting......................................................................................................... 78
Handling swollen rechargeable Li-ion batteries..........................................................................................................78
Dell SupportAssist Pre-boot System Performance Check diagnostics................................................................79
Running the SupportAssist Pre-Boot System Performance Check................................................................ 79
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