How to create a bootable USB drive for Operating System deployment on BIOS based systems (by Paul Marquardt)
This article describes a process to create a bootable USB drive which can be used to install the operating system onto your system. Transferring the installation files to a USB drive makes loading the operating system faster—consider that the DVD’s fastest transfer rate is 21 Mb/s compared to the USB native rate of 480 Mb/s. You can also load the operating system on tablets and other devices that support USB but don’t support optical media.
If you have a large enough USB drive, you can even copy multiple OS install files from separate media versions into different folders. When you want to install a particular OS, move the root files from the USB drive into their respective folder and move the desired install files to the root of the USB drive for installation. This makes changing install media very quick and painless. This method allows you to keep multiple copies of an OS on a single drive, i.e. Windows Server® 2012 Retail media, Windows Server 2012 OEM media, Windows Server 2012 Datacenter Edition VLK, etc. See Image 1 for an example.
The following steps will guide you on how to make the USB drive bootable and get the contents onto the drive.
5. Select your USB drive from the list returned (Disk 2 in this example) by typing Select Disk 2 and pressing ENTER.
6. Remove all data from the disk by typing clean (Note: This will destroy all of the data on the USB drive) and pressing ENTER.
7. Create a primary partition by typing create partition primary and pressing ENTER.
8. Create a bootable partition by typing active and pressing ENTER.
9. List all volumes recognized by the system by typing list volume and pressing ENTER.
10. Select your volume from the list (Volume 3 in this example) by typing select volume 3 and pressing ENTER.
11. Quick format the disk using NTFS by typing format fs=ntfs quick and pressing ENTER.
12. Insert your desired operating system media or mount your ISO.
13. Copy the entire contents of the installation media from the installation media to your USB drive.
You’re now ready to use the USB drive as installation media on your systems. Just boot to the USB drive and setup will begin, or just insert the USB drive and allow setup to auto run, or open setup from a file explorer window.