Hi @anon64481721 and @ricklinux,
to complete your steps :
- Reset BIOS to factory Defaults.
- Not necessary, it will goes itself on default after update… - Update it - Yes
- Start EndeavourOS
- not yet setup correctly your bios before to start Eos usb uefi live. Check uefi mode, select your UEFI SDD and UEFI usb key for boot + like @ricklinux told turn off secure boot and fast boot
- Start EOS UEFI USB live
- Build partitions myself
- with Gparted rebuild your head gpt partion SDD (we are agree that in doing it, you will loose all your data on your SDD)
- now create first partition sda1 550 Mb EFI and mark it as /boot/efi with flag esp format Fat32
- create sda2 20Gb or 30Gb partition system mark it as / format ext4
- create sda3 rest of the disk size mark it as /home format ext4
- Start auto-installer.
- yes your sdd is ready for install with Calamares
- build grub
- yes as @ricklinux told you check at the bottom of the install screen from Calamares where it is reporting it will install grub and put it on sda1
- Tell us if your EOS is flying on ?
