Computers/Latitude E5540

We own a set of 11 Dell Latitude E5540 laptops.

They were purchased from ComputerCorps in Carson City on 14 September 2023 for $1250: nominally 10 for $125 each, with an extra laptop with a missing battery thrown in free of charge.

Manufacturer	Dell
Model	Latitude E5540
Manufactured	8 December 2014
RAM	4 GB DDR3L 1600 1x 4 GB SODIMM, 1 slot open
CPU	Intel Core i3-4030U 1.9 GHz 2 cores
Graphics	Intel HD Graphics 4600
Storage	64 GB SSD
Optical	DVD+/-RW
Ports	HDMI (up to 3200x2000@60Hz) VGA 2x USB 3.0 type A 2x USB 2.0 type A 10/100/1000 Ethernet 3.5mm TRRS Headphone + Microphone SD Card
Display	15.6", 1366x768, touch
Size	14.92 x 9.86 x 1.32 in
Weight	6.13 lbs

Firmware

While the Dell logo screen is displayed during boot:

• Press F2 to enter the setup utility
• Press F12 for a one-time boot menu

Firmware Update

We should periodically check the Dell support site for new BIOS updates. We're currently using version A24 from 4 December 2019.

To update the BIOS without Windows:

1. Format a USB flash drive with a FAT32 file system
2. Download the Windows EXE for the BIOS update from Dell and put it on the flashdrive
3. Reboot the laptop, and on the Dell logo splash screen, press F12 to get to the boot menu
4. Select "BIOS Flash Update" from the boot menu
5. Click the "..." button to the right of "BIOS update file" and choose the EXE file
6. Click "Begin Flash Update"

Firmware Setup

These settings are recorded for BIOS version A24. Press F2 at the boot logo screen to enter setup.

1. Press the "Load Defaults" button
2. General
   1. Boot Sequence
      1. Set "Boot List Option" to "UEFI"
      2. Use the "Delete Boot Option" button to remove any options other than the primary OS
      3. Press the "Apply" button
   2. Advanced Boot Options: uncheck "Enable Legacy Option ROMs"
3. System Configuration
   1. Integrated NIC: set radio group to "Enabled"
   2. Parallel Port: set radio group to "Disabled"
   3. Serial Port: set radio group to "Disabled"
   4. SATA Operation: set radio group to "AHCI"
   5. Miscellaneous Devices
      1. Uncheck "Enable ExpressCard"
      2. Uncheck "Enable Hard Drive Free Fall Protection"
4. Security
   1. Admin Password: set the admin password
   2. Password Change: uncheck "Allow Non-Admin Password Changes"
5. Power Management
   1. Primary Battery Charge Configuration: set radio group to "Primarily AC Use"
6. POST Behavior
   1. Fastboot: set radio group to "Minimal"

Operating System

The laptops run Lubuntu 24.04 LTS.

Installing

1. Install using the Lubuntu live USB installer. Accept the installer's default settings except:
   1. On the Customize step, select "Normal Installation".
   2. On the Partitions step, select "Erase Disk".
   3. On the Users step:
      • Your Full Name: SNAFU Con
      • login: snafucon
      • Computer Name: snafucon-<instrument>
      • Password: standard device password
      • Login in automatically: yes
2. Remove default desktop icons and add Firefox to the desktop.
3. Start Firefox on boot: Start -> Preferences -> LXQt Settings -> Session Settings -> Autostart, Name: "Firefox", Command: firefox
4. Set up Firefox:
   1. Skip all steps in "Welcome to Firefox"
   2. Menu -> Settings
      1. Home and startup
         1. Uncheck "Open previous windows and tabs"
         2. Set "new windows" homepage to https://register.snafucon.com/atcon/
         3. In "Firefox Home" section, disable everything except "Search" and "Logo"
      2. Search
         1. Set default search engine to DuckDuckGo
         2. Disable "Suggest search engines to use" and "Suggestions from Firefox"
      3. Privacy and security
         1. Disable "Suggest Firefox Relay email masks"
      4. Passwords and autofill
         1. Disable "Ask to save passwords"
         2. Disable "Save and autofill payment info"
         3. Disable "Save and autofill addresses"
      5. Tabs and browsing
         1. Disable "Enable link previews"
         2. Disable "Recommend extensions as you browse" and "Recommend features as you browse"
      6. AI controls
         1. Enable "Block AI enhancements"
   3. Install the "uBlock Origin" extension, allow it to run in private windows
   4. On the new tab page, turn off the bookmarks toolbar.
   5. Customize the toolbar. From left to right: Back, Forward, Refresh, Home, URL bar, uBlock Origin, Downloads, Extensions (add Home, remove spacers, VPN, Account, move uBlock)
5. Install bacondevd using the .deb package on a USB drive.

Units

Each individual computer is listed by its Dell service tag (serial number).

328YP12 "My Son, He Has Every Disease"

This is our parts machine. It doesn't work.

Known Issues

• Screen has a bright blue stuck pixel in the upper left.
• DVD drive eject mechanism doesn't work.
• Ethernet port pins are mangled.
• SSD is failing – it intermittently just doesn't connect to SATA. Sometimes the BIOS says no boot device could be found, sometimes the BIOS finds it and starts the kernel but then it disappears and you get an initramfs panic prompt, sometimes it boots fine. If you get into the OS it seems to work reliably until the next reboot.

History

• 2026-10-05 took right IO module with bad Ethernet port from HW7YP12. (It would have been way easier to just swap the screen and DVD drive, but whatever.) --Sammich

44BYP12 "Kalimba"

Touchscreen Issue

This computer has a bad touchscreen – it sometimes gets into a state where it registers frequent false touch events in the same location. Moving the screen hinge can cause or resolve the issue. The touchscreen can't be disabled in the BIOS, so it has been disabled in Linux by creating /etc/udev/rules.d/95-disable-touchscreen.rules with the contents

SUBSYSTEM=="usb", ATTR{idVendor}=="04f3", ATTR{idProduct}=="0251", ACTION=="add", ATTR{authorized}="0"

History

• 2026-10-06 diagnosed mouse issue as bad touchscreen, disabled touchscreen with udev, returned to service --Sammich
• 2025-10-30 computer is receiving random mouse inputs with nothing connected, pulled from service --Elane

HW7YP12

Known Issues

• SSD is failing – it intermittently just doesn't connect to SATA. Sometimes the BIOS says no boot device could be found, sometimes the BIOS finds it and starts the kernel but then it disappears and you get an initramfs panic prompt, sometimes it boots fine. If you get into the OS it seems to work reliably until the next reboot.

History

• 2026-10-05 took right IO module with good Ethernet port from 328YP12. --Sammich