Ubuntu won't boot the first time. Why?

Question

linux

There was a problem with the computer, ubuntu does not boot the first time.
I turn on the computer, first a splash screen from the motherboard appears, where you can go to the BIOS, then a purple screen appears, without text, just a purple screen, after a second the screen goes blank, the monitor writes no signal. So you can wait indefinitely, nothing will happen.
If you reboot with the reset button 10-15 times, then at some point the system boots. But first the log appears on a black screen, then Ubuntu starts to boot. It takes a long time to load, 3-4 minutes, it usually takes 20-30 seconds to load.
On the computer is only ubuntu. Just in case, I checked all three disk partitions (EFI, swap and filesystem) with the help of sudo badblocks -sv /dev/sda1Bad sectors. Ubuntu version 15.10. Where to look for the reason?

Answer 1

less /var/log/syslog

Answer 2

It is very similar to a piece of iron problem in the form of dried up electrolytic conders. Old computer?? look at the motherboard and food for the presence of swollen.
I will assume a long loading due to checking the disks after the reset.