Ubuntu and UEFI on Lenovo Thinkcentre M92P

Lenovo Thinkcentre M92P.txt

Lenovo Thinkcentre M92P
When booting to USB installer disk installation proceeds as expected
1962 no operating system found
When booting into preview mode all disks load without issue, so its not the cable
Secure Boot option either not present or disabled
Last time I fixed this by adding a fake line to the boot loader from instructions on the web
Got a warning during installation about UEFI mode
Windows Fast Startup disabled

jfly comment below:
I ran into this issue on my Thinkcentre M92p and found that installing the latest bios update from 
https://support.lenovo.com/us/en/downloads/ds029265-flash-bios-update-thinkcentre-edge-92-thinkcentre-m82-m92-and-m92p-thinkstation-e31
(as of 2022-04-07, that's version 9SKT9CA released on 2018-12-23) makes UEFI booting work for me without having to futz with the names of the entries.

here's a list of prerequisites to run pc in uefi mode, like:
1) GPT partitioned disk (holds true if you want to run both win and linux)
2) efi partition with bootloaders
3) Bios is set to boot in uefi mode
4) efi vars are programmed
https://forums.lenovo.com/t5/Other-Linux-Discussions/ThinkCentre-M92p-Linux-Boot-Problem/td-p/871891

UEFI vs Legacy
https://askubuntu.com/questions/647303/uefi-or-legacy-which-is-advised-and-why
http://www.daossoft.com/bios-tips/how-to-switch-from-uefi-to-legacy-on-lenovo.html

[SOLVED] UEFI BIOS not recognizing Linux EFI Bootloader (Dual Boot)
https://www.linuxquestions.org/questions/linux-newbie-8/uefi-bios-not-recognizing-linux-efi-bootloader-dual-boot-4175619918/
https://www.lifewire.com/change-the-efi-boot-order-efibootmgr-4028027

https://itsfoss.com/no-grub-windows-linux/
bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi

HERE IS THE MAGIC LINK
https://forums.lenovo.com/t5/ThinkStation/UEFI-Mode-installation-of-Linux-distributions-on-Thinkstation/td-p/1018555

It appears that, prior to to following the BootOrder specified in the UEFI 
Boot Manager, the Lenovo BIOS first checks the UEFI Boot Manager 
configuration for an entry labelled "Windows Boot Manager".[1] 

More in the series of bizarre UEFI bugs
https://mjg59.dreamwidth.org/20187.html

How to install Linux on UEFI systems where GRUB fail to install?
https://forums.lenovo.com/t5/Linux-Discussion/How-to-install-Linux-on-UEFI-systems-where-GRUB-fail-to-install/td-p/674103

Delete EFI entry
https://unix.stackexchange.com/questions/223581/remove-windows-boot-manager

Using BootRepair
https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows

Kernel boot
https://wiki.ubuntu.com/DebuggingKernelBoot

If anyone else is still tripping over this, I found two approaches for installing the latest ubuntu server on the M91P:

1. Flash/upgrade the BIOS to the 2018 version, from this page: https://support.lenovo.com/us/en/downloads/ds029265-flash-bios-update-thinkcentre-edge-92-thinkcentre-m82-m92-and-m92p-thinkstation-e31. I used the "Flash from operating system version". This worked for one of mine, but I seem to have bricked another one. It stopped posting and stopped accepting input during boot. So YMMV.
2. Keep the old BIOS, instal an older version of Ubuntu server that doesn't expect UEFI support, and upgrade to the latest version. I started with Ubuntu 14.04 and upgraded all the way to 24.04. In the installer's "Partition Disk" step, I chose "Guided - use entire disk" and then on the "Install the GruB boot loader on a hard disk" step I chose Yes. It's tedious but seems to work.