Advisable to install with “UEFI-only” or “Legacy” BIOS setting on Lenovo Thinkpad?

Question

I got a new Lenovo Thinkpad. I'm preparing to install Ubuntu on the computer. The BIOS settings give me the choice of setting it to "UEFI-only" or "Legacy." I'd prefer to use UEFI-only because it's supposed to allow faster boot. But I don't know how well Ubuntu supports UEFI. Which setting is advisable?

Answer 1

1. If you already have an OS (eg Windows) installed in EFI mode, you must leave your BIOS in EFI mode.

2. If you already have an OS (eg Windows) installed in Legacy mode, you must leave your BIOS in Legacy mode.

3. Else, you can install Ubuntu in whatever mode you want. You can even try both modes and check if one is faster than the other.

Other remarks:

• EFI is best supported by recent 64bits (amd64 ISO) versions of Ubuntu, such as 12.04.
• you can convert an installed Ubuntu from EFI mode to Legacy mode (or contrary) via Boot-Repair's Separate /boot/efi option.

Answer 2

Ubuntu 11.04 (Natty) supports booting from UEFI as explained by this Ubuntu community wiki.

"From Ubuntu 11.04 onwards (x86_64 only), the ISO CD supports UEFI booting and the Ubuntu installer will try to setup the bootloader got (U)EFI boot."

If you are dual booting with Windows - make sure you are using Windows Vista (SP1 + 64bit) as the minimum.