How to convert a PC from BIOS mode to UEFI mode

Upgrading your Windows 7 PC to Windows 8 and considering the Unified Extensible Firmware Interface (UEFI) mode? If your PC supports it, this is a great time to change to UEFI. Why? UEFI mode can help your PC start faster, lets you use hard drives larger than 2 terabytes (TB), and can help you set up features like Secure Boot. Many Windows 7 PCs support UEFI but were set to boot to BIOS mode.

To switch to UEFI mode, you’ll need to do a few things: find the setting in the boot menus that enables UEFI booting, convert the entire drive to the GUID Partition Table (GPT) format, and install Windows again.

Step 1: Find the setting in the boot menus that enables UEFI booting

  • This differs from PC to PC. But typically, you press a key to enter the boot menus, look for an option like "UEFI Boot Mode", and enable it.

Step 2: Boot the Windows Setup disk in UEFI mode

  1. Load the Windows 7 or Windows 8 DVD. (If you’re setting up a dual-boot PC, install Windows 7 first.)
  2. Start the PC to boot the DVD in UEFI mode. Again, this is going to depend on your hardware, but often you can press a key during the boot sequence, and select an option like "EFI DVD/CD".

Step 3: Convert the drive to the GPT format

  1. When the Windows Setup program gets to the first set of installation screens, press Shift+F10 to open the command prompt.
  2. Figure out which disk is your primary hard drive, and select it. Typically it’s Drive 0, but it doesn’t hurt to check:
    diskpart
    list disk    review the list of drives, and make sure you’ve got the right one.)
    select disk 0
  3. Erase the hard drive, and convert it to the GPT format:
    clean
    convert gpt
    exit
  4. At this point, you can switch back to the installation program, and continue the Windows installation. Windows automatically sets up the partitions for the UEFI/GPT format.

See also: Dual-booting your PC (Windows Hardware Newsletter, November 7, 2012)

Author: Robert Smit [MVP]

Robert Smit is Senior Technical Evangelist and is a current Microsoft MVP in Clustering as of 2009. Robert has over 20 years experience in IT with experience in the educational, health-care and finance industries. Robert’s past IT experience in the trenches of IT gives him the knowledge and insight that allows him to communicate effectively with IT professionals who are trying to address real concerns around business continuity, disaster recovery and regulatory compliance issues. Robert holds the following certifications: MCT - Microsoft Certified Trainer, MCTS - Windows Server Virtualization, MCSE, MCSA and MCPS. He is an active participant in the Microsoft newsgroup community and is currently focused on Hyper-V, Failover Clustering, SQL Server, Azure and all things related to Cloud Computing and Infrastructure Optimalization. Follow Robert on Twitter @ClusterMVP Or follow his blog https://robertsmit.wordpress.com Linkedin Profile Http://nl.linkedin.com/in/robertsmit Robert is also capable of transferring his knowledge to others which is a rare feature in the field of IT. He makes a point of not only solving issues but also of giving on the job training of his colleagues. A customer says " Robert has been a big influence on our technical staff and I have to come to know him as a brilliant specialist concerning Microsoft Products. He was Capable with his in-depth knowledge of Microsoft products to troubleshoot problems and develop our infrastructure to a higher level. I would certainly hire him again in the future. " Details of the Recommendation: "I have been coordinating with Robert implementing a very complex system. Although he was primarily a Microsoft infrastructure specialist; he was able to understand and debug .Net based complext Windows applications and websites. His input to improve performance of applications proved very helpful for the success of our project