@someoneFromInternet let me know if the issue will resolve after an update.

@someoneFromInternet looks old. Current BIOS version is 1.52.

You may have bugged version of thunderbolt controller as well.

Run fwupdmgr get-devices as root to check Thunderbolt Firmware version. Find "T480 Thunderbolt Controller" in output and check "Version" parameter.

It should say "20.00" or higher. If it's lower then I highly recommend you to upgrade your firmware ASAP!

Install fwupd and run these commands to update your firmware (run as root):

fwupdmgr refresh  
fwupdmgr update   

For more info check out this wiki page:
https://wiki.archlinux.org/title/Fwupd

@someoneFromInternet what BIOS version do you have? You can update firmware on T480 without USB stick. Use fwupd util.

@CorrodedCranium if you can afford a 600$ computer, maybe Framework will be a decent choice?

@pastermil X230 had it for a long time. But you have to do a BGA rework, 'cause CPU is not socketed like on T-series of that era.

@monovergent

@promitheas Never heard about battery whitelists on T480. What BIOS version do you have?

Also there is a reset button in the bottom of the laptop near ThinkEngine controller: Power off the laptop, disconnect both batteries and CMOS and hold reset button for a minute.

@velox_vulnus no, there are no battery mods for 80 series.
It also has no CD/DVD that you can swap for 2nd drive or so.

I recommend you to watch a T480 review with disassembly first.

@velox_vulnus T480 owner here.

Don't expect T480 with i7 to actually run 4 GHz all times when needed. Get an i5 model instead.

I have i5-8350U. The best frequencies I could get on heavy load are 3.5-3.6 GHz (dGPU heatsink + PTM7950). Still throttles but not so much.

T480 has excellent battery life with both 24 + 72Wh batteries. What was the main reason why I got it.

My laptop wasn't refurbished. I got it used without some parts - SSD and both batteries. Then I bought all parts by myself.
It could be cheaper to refurb it by yourself rather than by someone else.

@awesome_guy does keyboard has any logo on the left side of Space key? If no then keyboard is not backlit.

Does keyboard backlit works in UEFI? It should.

Also remove your keyboard using Hardware Maintenance Manual for L440 and look for backlit cable, it could be damaged or poorly connected.

@schizoidman I saw X270 and X230 mods on Reddit that replaces Lenovo's power connector to USB-C.

@Jumuta Skulls just uses SeaBIOS as a payload, so it mush simpler.

However you can still try Libreboot, but you need to dump your firmware and extract binary files from it (like IME for example, and vgablob if you have Nvidia GPU)

@Jumuta try Coreboot from Skulls project

@Jumuta if your laptop doesn't turn on, external flashing is the only way.

@kanzalibrary