UEFI stands for Unified Extensible Firmware Interface. It was developed as a new alternative to BIOS that has been around for generations. BIOS checks the hardware in your computer and loads all needed information and then passes the steering wheel to the operating system.
What is the purpose of UEFI?
The predecessor of UEFI, BIOS, was created by Intel specifically for Itanium-based servers. Being a product of the previous era, BIOS has many limits such as 16-bit architecture and only 1MB of addressable space. In addition to that, it used the Master Boot Record partition scheme. With these constraints including a limited amount of RAM that can be put to good use and inability to “read” HDDs more than 2.2TB, it was clear that we need a more advanced solution for the same purpose.
That solution was also presented by Intel – they called it Intel Boot Initiative. Later it was renamed to EFI and then evolved into UEFI we know today. The original version of the EFI interface is available only on Intel processors but can be used in Macs. With the invention of UEFI, AMD processors also received an invitation to the new interface.
Advantages of UEFI
The biggest advantage over old BIOS is the support of 32-bit and 64-bit architecture. This allows allocating more RAM for more complex processes that were impossible to execute in BIOS. Also, UEFI can handle independent drivers and CPU independent architecture. Another important improvement was the addition of the new user-friendly interface with mouse support. In BIOS you had to use arrow keys to navigate between tabs and menus.
UEFI support the older MBR partition scheme and the newer GPT. This GUID partition table comes with a few major enhancements such as 128 partitions (instead of 4 with MBR) and increased partition size to 9.4 zettabytes (1ZB = 1 trillion gigabytes) when MBR is limited to 2.2TB.
UEFI’s boot manager allows you to forget about a separate boot loader. Extensions such as ACPI are also supported in UEFI despite the fact they are not 16-bit. As a bonus, UEFI speeds up the startup process and has better networking support.
Today, when progress never rests, BIOS quickly becomes insufficient to the point of extinction as it cannot keep up the pace with capacities of modern computers and their power. UEFI, on the other hand, shows promising results and will probably stay with us for at least one or maybe even two decades.
Now you understand the advantages of using UEFI instead of BIOS on your computer. Things like faster shutdown and quick startup are really noticeable on UEFI-enabled devices. And here a brief rundown of other great UEFI features:
- Secure Boot: your operating system now has a pre-boot process to protect it from malware, virus attacks, and bootkits.
- ELAM driver: Secure Boot also loads the Early Launch Anti-malware process to check all non-Microsoft drivers before the system loads them into memory.
- Windows Trusted Boot: adds additional protection for the kernel/system drivers during launch.
- Measured Boot: measures all components of the system (including firmware and boot start drivers) and stores the data in the TPM chip.
- Device Guard: a virtualization-based tool for protecting code integrity.
- Advanced security protection (NTLM hashes, etc.) with tools like Credential Guard that utilize TPM support as well as CPU virtualization.
- BitLocker Network Unlock: automatic Windows 10 unlocking at reboot after you connect to a corporate network.
- GUID Partition Table for working with large boot disks.
It is not all, of course, but it is enough to convince us that all manufacturers should sooner or later switch to UEFI and leave BIOS to rest in peace.