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Whenever I switch my old Dell E520 on first thing in the morning it fails to boot into Ubuntu 16.04. It gets through bios to grub & beyond but will stop while trying to load the os. It finishes at a black screen. This seems a common problem & I've tried all the suggested solutions appropriate to my setup from the My computer boots to a black screen, what options do I have to fix it? thread, but none have worked for me.
What seems different from any other solution or discussion offered is that I have found a strange workaround: if I get to grub & run memtest for a minute then press esc to reboot, all is well! This works every time.
My questions are: Can anyone suggest why this works? Is there a solution that does not need my intervention at grub?