Select Page

BIOS boot modes, something that is so long standing in the IT industry which never changes, it had a single option which was the BIOS boot mode. The usual blue screen that only works with a keyboard and not a mouse, the blue screen that you have to access from the black screen on boot usually by repetitively tapping on either the F10, F2, F12, F1 or DEL key, depending on your motherboards manufacturer. Simple right? No. It’s an absolute nightmare.

But hey, we’ve got a newer and upgraded version of BIOS, and it’s called UEFI. UEFI was actually launched officially as a standard back in 2006 believe it or not. The time from when a standard is launched vs how quickly this moves throughout the IT hardware manufacturers is often measured in years, not months or days. So actually this is a fairly ‘new’ thing and many consumer hardware manufacturers only started to phase this technology into their systems around 2017.

The whole point of UEFI is the concept of Firmware-as-a-Service which is focused around extensibility rather than fixed approaches. What this means is that UEFI is designed to allow the utilisation of large disk partitions of over 2TB in size along with a modular design which enables both backwards and forwards compatibility.

Fundamentally the difference between BIOS and UEFI comes down to the link between the hardware and boot loader layer on your drives and bootable devices connected to your system. Think of this kind of like the ‘Construct Program’ in The Matrix – you can load whatever you want, given the constraints of the system.

In the real world what this means is that traditional BIOS systems are based on a more simplistic limited memory/capacity systems of computer chips. Whereas UEFI is capable of operating on systems that have more advanced hardware chips within their systems. Hardware and software are intricately linked. UEFI stands for Unified Extensible Firmware Interface.

One of the huge benefits from a user perspective is that within UEFI you can actually use your mouse to control the system rather than everything being keyboard driven in the Legacy BIOS system. Beyond that, you are probably never going to need to worry about these differences – that is until something doesn’t work as you expect in relation to a piece of hardware not booting correctly. This is where things are a bit messy and it’s going to take likely another decade until things fully iron their self out.

As a general rule of thumb, for modern hardware, just use UEFI to Boot. For older hardware or older operating systems, you may have to use Legacy Boot to get the machine to boot up successfully.

Rather than re-invent the wheel, here is a handy source of the core differences between Legacy Boot mode and UEFI Boot mode;

What is a difference between UEFI and Legacy Boot settings;

  • Legacy is traditional and very easy method which had worked absolutely fine so far.
  • UEFI is critical, 1709 was the first perfect OS which worked best with the OS.
  • Legacy has best in performance had minimum boot issues and easiest to install.
  • UEFI is now stable, but yet most of the IT tech do not now how to use this feature and correctly install the OS.
  • Legacy was safe and secure and very user friendly, it is just that you can select the boot device which you want to boot from and it search for Master Boot Record MBR and used to pick it up.
  • UEFI is market as more secure but there is no more security just that it supports TPM which enables Bitlocker and has extra headache to mention the EFI boot manager, which is no secure if you have access to BIOS and did it few times earlier just like Legacy.
  • Legacy has maximum partitioning size of 2 Terabyte.
  • UEFI has partitioning size of 9 Zetabyte which is huge.
  • Legacy can have 4 Primary Partition.
  • UEFI can have 128 Primary Partitions.
  • Legacy is good for loading 2 OS on same system.
  • UEFI is Great for loading more than 2 OS on the single system.
  • There are more differences and UEFI is way beyond the Legacy BIOS technology but it has not yet revealed its troe power.
  • Legacy uses Master Boot Record.
  • UEFI uses GUID Partition Table.
  • Legacy is traditional Firmware which interacts with Motherboard and OS.
  • UEFI is also just a Firmware with advanced options.
  • Microsoft New OS will no more support Legacy they have transformed now.
  • Microsoft stop support for Legacy OS after launch of 1709 WIndows update.
  • The last best Hard Drive supported by Legacy BIOS is SATA SSD.
  • The Last Best Hard Driver supported by UEFI is M.2 PCIE SSD Hard drive which does not work on Legacy BIOS.
  • Legacy Supports the SSCM in traditional way like you can enable PXE boot and select option to Boot From Network through LAN.

UEFI also supports and enable options to boot from traditional network which is IPV4 as well as IPV6. UEFI firmware is keeping all possibility of future options. To enable it you need to enable UEFI Network Stack which will give option for IPV4 and IPV6.

The following two tabs change content below.

Michael Cropper

Founder & Managing Director at Contrado Digital Ltd
Michael has been running Contrado Digital for over 10 years and has over 15 years experience working across the full range of disciplines including IT, Tech, Software Development, Digital Marketing, Analytics, SaaS, Startups, Organisational and Systems Thinking, DevOps, Project Management, Multi-Cloud, Digital and Technology Innovation and always with a business and commercial focus. He has a wealth of experience working with national and multi-national brands in a wide range of industries, across a wide range of specialisms, helping them achieve awesome results. Digital transformation, performance and collaboration are at the heart of everything Michael does.