Fix: “Initramfs unpacking failed” while trying to install Ubuntu Server in Virtual Box

Just posting a fix that took me hours of googling. While trying to install Ubuntu Server 20.04 on Virtual Box 6.1, and after mounting the Ubuntu Server ISO then starting the VM, I encountered this error:

Screenshot of the boot error

Turns out I reduced the RAM of the VM to be 512MB, adjusting the RAM to 768MB fixed it!

Thanks to @mrtumnus for posting his answer at serverfault:
https://serverfault.com/questions/1033384/qemu-ubuntu-server-20-04-initramfs-write-error

Hope I saved you some googling time!