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UEFI BIOS explained

Posted on 3 May 2013 at 07:23

You can also leave Secure Boot enabled and manually authorise other operating systems' bootloaders, in addition to the Windows 8 one. For example, you might add a key for Ubuntu to the Secure Boot database, enabling both Windows 8 and Ubuntu to start, while continuing to disallow other, unknown operating systems. The precise process for generating a Secure Boot key should be detailed in the manual for your motherboard or laptop, or in the installation instructions for the operating system.

What’s more, Microsoft has agreed to allow other recognised operating system publishers to use the same bootloader key as Windows 8 (for a fee). Fedora Linux has already done this, so you can install and boot Fedora on a Windows 8 system with no additional configuration required.

The advantages of Secure Boot

Not only is Secure Boot not harmful, it can be greatly beneficial, both at home and at work. For businesses, it can help to enforce security policies. If users are able to plug in their own hard disks and boot into unauthorised operating systems, they could bypass restrictions on which software can be run, what sort of network access is permitted and so forth. If the IT department uses Secure Boot – and a password protects the UEFI settings, to prevent them from being tampered with – the potential for data leaks is greatly reduced.

For home users, Secure Boot can protect your security in a different way. Here, the major risk isn’t from corporate spies, but from malware. Secure Boot protects your system against rootkit-type infections that infect the bootloader and effectively make themselves hypervisors for the operating system. If unrecognised startup code can't be executed, infections like this are stopped in their tracks.

Before we go overboard singing the praises of Secure Boot, there’s one catch we must point out. We mentioned above that Secure Boot could be disabled on x86 hardware. However, if you buy an ARM-based Windows RT device, you won’t be able to disable Secure Boot: on this platform, the feature is permanently locked on, and all third-party bootloaders are strictly banned. You can see why Microsoft insists on this: it ensures that consumer tablets provide a completely seamless and consistent experience, with no possibility of malware or confusing multiple environments. However, it’s bad news for anyone hoping to install Android or Linux on Windows tablet hardware.

What's in a name?

The rise of UEFI raises questions about terminology. As we've noted, the term “UEFI BIOS” is arguably misleading, since the UEFI system completely replaces the classic PC BIOS.

However, the combination of UEFI and the underpinning firmware does constitute a “basic input and output system”, albeit not of the specific sort that’s typically referred to by the term “BIOS”. Alternatively, you might take the view that the firmware itself is a BIOS, and the UEFI is merely a shell that sits on top of it. Either way, the use of the term BIOS isn’t exactly wrong, and as long as the term UEFI is present as well, the meaning should be clear.

Another question is how to pronounce UEFI. Although the Unified EFI Forum has published voluminous standards material, it hasn’t provided any official guidance on this burning issue. Here at PC Pro we tend to say “weffy”, but Microsoft internally spells the term out as “U-E-F-I”. Another possibility is “you-fee”, or perhaps, for football fans, “you-eh-fee”. Whichever pronunciation you choose, get used to defending it: if the ongoing lack of consensus on “SATA” is any guide, pronunciation arguments over UEFI will probably be with us for at least as long as the technology itself.

Author: Darien Graham-Smith

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User comments

While UEFI does provide benefits, so far my experience hasnt swayed me to prefer it over bios.

The first issue is that it isnt as flexible as bios, for example, it cannot apparently chainload as well as bios systems can. Of course this can be fixed but I doubt oems will do this as well as they should or require kludges to work.

The second issue is that its can be more easily damaged, for example Ive seen a w8 laptop which could no longer access the setup menu or the boot device menu.

Now again I am going by what I have seen and these are oem laptops but i havent really used it on my desktop as my gpu doesnt support it and i multi boot other oss.

By tech3475 on 3 May 2013

I think you failed to mention one of the major plus points and one of the benefits. Speed, BIOS takes time to go through its testing processes, whilst UEFI allows booting within UEFI, check a UEFI motherboad, install windows 7/8 in UEFI mode or osx, and you will see it boot up a lot quicker, intergrating bootscreen and UEFI together.

By jamieostrich on 3 May 2013

Great Artical

A very interesting read. Thank You.

By Ken_H on 4 May 2014

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