Step by Step UEFI Boot Device

Have you noticed that new PCs and tablets seem to boot really, really quickly? Compared to your typical work desktop, these devices are up, running, and ready to logon in seconds! No longer is there time to go get a coffee and come back  to see the Username/Password prompt flash into existence. How does it boot so quickly? That’s due to the Unified Extensible Firmware Interface (UEFI). Once UEFI is enabled, it allows us to get around the limitations of the Basic Input Output System (BIOS) that has been around in one form or another since 1975. Those limitations included 16 bit processor mode, and being limited to 1 MB of addressable space. UEFI also uses a newer partitioning scheme, GUID Partition Table (GPT). GPT was designed to extend pass older limits. In this case, Master Boot Record (MBR) is limited to a maximum disk size of 2TB.

How does all this fit together? Well, to install a modern operating system (OS), a UEFI bootable device needs to be created. If you’re booting from a Windows 8.1 DVD, and UEFI is enabled in the BIOS of your pc, the required partitions are automatically created. If, however, you’re using the Windows 8.1 iso downloaded from Microsoft, then you need to build a bootable device yourself. This means using FAT32, I repeat, you need to use FAT32, *not* NTFS! The following screen shots and explanations will give you all the detail needed. Read through all the steps first, backup your old OS, then start playing.

First, choose an appropiately sized USB Flash Drive, in my example I’m using an old 32 GB Patriot Flash Drive. Insert it, then run diskpart from an administrative command prompt:


Note the Disk number for your USB disk, in this case Disk 1. Then type the following command: select disk 1

select disk 1

diskpart’s focus is now on Disk 1, let’s remove everything from that disk using: clean


next we’ll use GPT instead of MBR: convert gpt

convert gpt

let’s make a primary partition and then format it, note you’re using FAT32:

create primary partition

looks like it worked, now to check by using: list volume

List Volume

looking good! We now have a FAT32 partition on a GPT disk. Exit diskpart, taking *careful* note of the drive letter. In the screenshot above, the * symbol is showing next to Volume 3, with a drive letter of “F”. The next step is to copy bootsect.exe from the desired operating system media. To do this, double click on the iso (or browse a DVD) and find bootsect.exe, under /boot:


copy bootsec.exe then type the following: bootsect /nt60 f: (or whatever drive letter you *carefully* noted above!)


next, copy the entire contents of the iso or DVD onto your newly formatted, bootable flash drive:


Once the copy process is completed, you should have a brand new USB FAT32 GPT bootable device. Follow the instructions to enable UEFI boot in your BIOS, reboot using the above mentioned USB and install a really, really fast booting version of your operating system. Even faster if you use an SSD. Good luck, and don’t forget to back up first!


Wayne McGlinn


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