Hi, I just did my first Linux install (Kubuntu) onto an external NVME drive. It boots fine on my laptop but gives me a “MBR error, insert floppy” screen when I try to run it on my desktop. On the motherboard settings the drive shows as a bootable option but without a UEFI label. What issues could cause this? From what I’ve read it seems like a boot loader problem but I have no idea why it would be fine on one device but not another. I tried to update the motherboard firmware but the file the manufacturer provides wasn’t working. It’s running a 2021 version.
The motherboard will only give me the option to use linux if it’s in legacy mode. In UEFI only mode it doesn’t show up.
Is secure boot turned on? If so you will probably need to turn that off. EFI boot entries get set in the UEFI somehow, so once you get it booted it should see it. But how old is the PC? Could be a limitation if it is old.