I installed Ubuntu 20 on my Dell Precision Tower 3620 and now it won't boot. Here's the sequence of events:
- I put the Ubuntu installer on a USB stick using Rufus and booted Ubuntu successfully from that, using the "Try Ubuntu" option.
- I installed Ubuntu on the PC, using the default options to wipe the disk and create new partitions.
- Ubuntu booted successfully. It prompted me to install updates and reboot, which I allowed.
- The PC failed to find a boot disk. (It attempted network boot, which is one of the later options in the BIOS boot sequence.)
- I rebooted and hit F2 for the BIOS setup. I changed the boot options to use UEFI, which listed "ubuntu" under it. I saved the options and rebooted.
- On rebooting, PC showed the black-and-white Dell logo, with a spinning circle under it, and "ubuntu" at the bottom of the screen. It stayed like that for at least 10 minutes. Power cycling and trying again didn't help.
- Hitting F2 for the BIOS setup, or F12 for the one-time boot menu no longer has any effect. It goes immediately to the Dell logo/spinning circle/ubuntu screen and stays there.
- Using the jumper on the motherboard to reset the CMOS got it back to the state where it fails to find a legacy boot disk, and I can use the one-time boot menu to boot Ubuntu. But presumably, it would stop booting again if I selected the UEFI boot as default.
Do I need to do something else to get it to boot Ubuntu from UEFI by default?
