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This question already has an answer here:

Is there any test that I can run to figure out if my BIOS is a legacy one or a UEFI/EFI BIOS?

It looks like it's a legacy one: there's no fancy window but only ugly white words on blue background, and I can't use mouse, BUT I get an EFI SHELL running after download a bootmgfw.efi and other .efi), extract to my USB and boot from the USB.

My questions are:

  • 1. How do I test whether my BIOS is UEFI or legacy?
  • 2. Will the EFI SHELL run if it's a legacy BIOS?
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migrated from Aug 15 '11 at 8:48

This question came from our site for professional and enthusiast programmers.

marked as duplicate by Ƭᴇcʜιᴇ007, Dave M, TFM, n0pe, Julian Knight Mar 7 '13 at 15:17

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With what programming language and environment? – Delan Azabani Aug 15 '11 at 8:32
up vote 2 down vote accepted

Don't expect the firmware to use clicky icons and fancy windows, whether it be legacy BIOS or UEFI; both are limited in size and resources, and frankly white-on-blue text is as good configuration interface as any. (It's not something you reconfigure daily, after all.) My ASUS laptop uses UEFI, but the configuration screen looks exactly the same as the one of a BIOS, and the firmware remains compatible with legacy bootloaders.

A good test is to run an EFI program in *.efi format. If you can successfully start it, then your computer supports UEFI.

Another way is to boot from a Linux CD, insert the efivars module (sudo modprobe efivars), then install and run the efibootmgr tool. If the module works and sudo efibootmgr lists the boot options, you have UEFI.

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However some UEFI systems may completely disable external access to UEFI and only allow access from the BIOS emulation part. For example this is often done on laptops that use Insyde H2O UEFI. – AndrejaKo Aug 15 '11 at 9:25
Seems that it's a efi/uefi bios and i've reinstalled win7 on GPT, using efi shell. The weird thing is there's no normal access to uefi, no "uefi option" in bios. the only thing i can do is to use a usb with efi shell files to get into the efi shell environment. – Eric Aug 16 '11 at 8:06
AFAIK, it's normal -- UEFI is just like BIOS in that it 1) boots the system and 2) provides a configuration interface; nothing really special. When you boot Windows using EFI, or when you are reconfiguring the system, you are "accessing UEFI". And the EFI shell is an external program, not a core part of UEFI. – grawity Aug 16 '11 at 8:27

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