I know a lot of posts have been written, and I had read most of them when I encountered the problem. None of them solved the problem.
I have successfully installed Ubuntu 12.04 on top of Windows 8. Now my PC simply boots into Windows 8.
If I press 'Esc' at start of BIOS, and then F9,the GRUB shows up and Ubuntu is listed at the top of the several options to boot from.
I did run Boot-Repair once I logged into Ubuntu explicitly from GRUB as mentioned above. I did all said by Stormvirux in this link, but was still unsuccessful.
The debug info is listed here.
Something which confuses me is the message which Boot-Repair stated after it did its job.
You can now reboot your computer.
Please do not forget to make your BIOS boot on sda (8004MB) disk!
The boot files of [The OS now in use – Ubuntu 12.04.2 LTS] are far from the start of the disk. Your BIOS may not detect them. You may want to retry after creating a /boot partition (EXT4, >200MB, start of the disk). This can be performed via tools such as gParted. Then select this partition via the [Separate /boot partition:] option of [Boot Repair]. (https://help.ubuntu.com/community/BootPartition)
I don't know why it says it is far from the start of the disk as I see it first in the GRUB menu which comes up at startup.
One more input, when I try to place the GRUB in sda, Boot-Repair does not progress giving me the following error:
GPT detected. Please create a BIOS-Boot partition (>1MB, unformatted filesystem, bios_grub flag).
This can be performed via tools such as Gparted. Then try again.
Alternatively, you can retry after activating the [Separate /boot/efi partition:] option.
I had to select Separate /boot/efi partition: sdb2
Best Answer
According to your description, you have correctly installed the GRUB bootloader in UEFI mode. You do not need any BIOS-boot partition, nor any other partition change.
The only remaining issue is to set up your BIOS (UEFI firmware) so that it boots by default the GRUB entry instead of the Windows entry. In other words, we need to find a way so that you won't need to press 'Esc' then F9 to reach the GRUB menu.
To perform this, please:
Boot order
' menu in your BIOS, and try to place the "Ubuntu
" entry first. Then save the change and reboot. If GRUB still does not appear by default, please follow step 2 below.Boot-Repair
-->Advanced Options
--> tick theBackup and rename the Windows EFI files
option --> Apply. Tell us the new URL that will appear, reboot, and tell us what you observe. The PC should now boot directly onto the GRUB menu.