I have just installed Ubuntu using ubuntu-16.04.4-desktop-amd64.iso
. I had Endless OS on my lepton and I decided to overwrite it by Ubuntu.
Now, when I start my laptop, I first see "acer" logo, then, for a second I see a purple screen and then black screen.
What can I do to bring my new laptop back to the operational state?
There is a open bug that causes random hard CPU lockups (caused by intel-microcode), some during the boot process (which makes it difficult to troubleshoot). Try starting it with dis_ucode_ldr grub parameter.
More in the bug report: https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1759920