Lenovo Thinkpad L460 hangs on boot

Hello everybody,
strange problem with this laptop. On all my other machines UM 20.04 LTS can be installed (and all other Ubuntu flavors as well) but on the Thinkpad L460 it's not possible to boot the ISO of any Ubuntu 20.04 flavor. Right now I am writing this post on my L460 with UM 21.04 beta.

Seems to be a kernel problem, right? Any input highly appreciated.
Though UM 21.04 beta runs well, I am more in love with LTS.

Hi :slight_smile:
Did you try different boot modes in BIOS like UEFI / legacy / both ?

Thanks for the reply.
Yes, I have done that. There is also the problem that I need to use the adapter. Without it nothing would happen, just a black screen.

Ahhh, means it looks booting but with black screen ?
Maybe something around graphical card. What is your exact config ?

Hello Olek,

thanks again. I googled a little bit. It's a classy problem.
Exactly what you have written happens during my boot, look at this funny output for the graphic card of my laptop:

llvmpipe (LLVM 11.0.1, 256 bits)

I am sure it's just a command line to solve it.

Further info: Skylake GT2 [HD Graphics 520]

Are you able to edit the boot options inside grub menu ?
If yes, you can try to remove quiet splash nomodeset as they found out here :

Now I have done that. It took a little bit of time.
Here is the new output:
GRUB_CMDLINE_LINUX_DEFAULT=""
GRUB_CMDLINE_LINUX=""
Right?

Olek,
we are close to a final solution. Here is the new output of my machine:
Mesa Intel® HD Graphics 520 (SKL GT2)

That´ s good news, thank you. But i can't boot without AC Adapter.

Are you able to post a picture of the whole command ?

(I think the config he is giving is more to reconfigure this grub option but once installed - the syntax is a bit different in this config files)

Nice to know :slight_smile: , sorry responded before I saw your 2nd answer xD
Maybe with this added to the boot option : dis_ucode_ldr

Now my grub is empty. Oh Lord, I guess, there is a new install to be done?

No, I don't think so :slight_smile: just stop the machine and start it again, we didn't saved something.

Here again but the grub is empty. I have been able to boot but that is beyond my knowledge.

Olek,
I am doing a clean install. I feel bad to waste your time. It was a test for me and I am sure i will be back soon.

Sure :slight_smile: go ahead :slight_smile:
I'm here to help don't worry :slight_smile:

Thanks for your kind words and the help. This machine is really messed up, no FN keys work properly, no boot on battery mode, the INTEL hybrid graphic card is not detected.
I have two laptops with Ubuntu Mate (working fine) and this L460 does only accept Debian right now. I am trying again a few days later to install UM on the L460 but I am busy at work and have to finish a project.