I created a Ubuntu Gnome 16.04.03 (64 bits) bootable usb using Startup Disk Creator and I am wondering whether there is a way (maybe with Gparted) to check if it is a BIOS or UEFI boot.

Checking the USB with Disks (Ubuntu 16.04), this is what I see:

First Partition of USB

Second Partition of USB

As you can see, in the Second Partition it says: Partition Type EFI(FAT-12/16/32). Does this mean this is NOT BIOS?


  • It should work in both modes. – user692175 Aug 19 '17 at 16:29
  • Unless you modified the Ubuntu iso, it is able to boot both in UEFI or Legacy BIOS mode. – Byte Commander Aug 19 '17 at 16:32
  • But how do I ensure that it will install UEFI – Francisco Aug 19 '17 at 16:33
  • That depends on whether you boot it in UEFI or in Legacy BIOS mode. There has to be a setting in your UEFI setup menu or boot menu. – Byte Commander Aug 19 '17 at 16:36
  • Ah..cool..cheers. I a bit new to this. – Francisco Aug 19 '17 at 16:36
  1. Depending on how you created the USB boot drive, it works in both [U]EFI and BIOS (alias CSM alias legacy) mode. If you clone the iso file to the USB drive, it will boot in both boot modes. In the original question I can see the iso9660 partition, which indicates a cloned system. And you set the boot mode in the UEFI/BIOS menu system, which is part of the computer.

  2. You may want to test if your live system is running in UEFI or BIOS mode. An installed system and a live system too is using the directory /sys/firmware/efi, so you can run the following command line,

    test -d /sys/firmware/efi && echo efi || echo bios
  3. Please notice that you will install a system, that works in the current boot mode,

    • If you install in UEFI mode, the installed system will work in UEFI mode
    • If you install in BIOS alias CSM alias legacy mode, the installed system will work in BIOS mode.
  • That was helpful..cheers – Francisco Aug 19 '17 at 16:51
  • Let us know how it works for you to install Ubuntu Gnome. Good luck :-) – sudodus Aug 19 '17 at 16:53
  • Sure.. I'm still in the process of understanding the partition scheme, as it seems that I am suppose to create an ESP partition. (I am manually partitioning since I want to install windows later on..I am aware of the problems that might arise from this procedure as I've heard I'll have to do a boot repair) – Francisco Aug 19 '17 at 16:57
  • 1
    @sudodus Yeah, isn't it simpler to run grub-install rather than boot-repair? – wjandrea Aug 19 '17 at 17:07
  • 1
    Yes, @wjandrea, for you and me, but a new user might prefer a GUI tool. But I think the best option is to avoid reinstalling the bootloader ;-) – sudodus Aug 19 '17 at 17:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.