Article Number: CPU-UEFI-Mode

For users running the AMD Ryzen™ Processor with Radeon™ Vega Graphics, AMD strongly recommends that your motherboard firmware (“UEFI”) be configured full UEFI Mode to ensure optimal performance, compatibility, and stability with the Windows® 10 operating system.

What is UEFI?
Unified Extensible Firmware Interface (“UEFI”) can be thought of as a tiny operating system that resides on your PC’s motherboard. Tiny operating systems for a piece of hardware are called “firmware.” UEFI firmware provides critical functions to your PC: initializing and booting the processor, detecting and training memory, configuring data buses and motherboard peripherals, monitoring and controlling core hardware, changing low-level settings, and helping Windows® communicate with your PC components. UEFI replaces an older and simpler standard called “BIOS,” though many people today still informally refer to a motherboard’s UEFI firmware as “the BIOS.”

How are UEFI and BIOS different?
Compared to the older “legacy” BIOS firmware, UEFI firmware offers many new and useful features, including

  • Greatly improved security
  • Fully specified interfaces that ensure interoperability and testability
  • Dependable firmware updates from the internet with minimal user interaction
  • Support for hard drives larger than 2.2TB
  • Support for many new types of HW, including NVMe SSD boot support
  • Windows® 10 Secure Boot for malware prevention
  • Faster shutdown, startup, sleep, and resume times

Because of these powerful benefits, the AMD Ryzen™ Processor with Radeon™ Vega Graphics is intended to be used in full UEFI Mode when paired with the Windows® 10 operating system.

What is UEFI Mode?
The PC industry’s transition from BIOS to UEFI is still ongoing, and not all hardware in the market—especially older hardware—understands how to communicate with UEFI firmware. For this reason, motherboards with UEFI firmware can toggle between two modes: UEFI Mode and Legacy Mode. Legacy mode emulates some aspects of the older BIOS standard by disabling many of the advanced performance/security/reliability features of UEFI Mode. In other words: compatibility with older hardware is maximized, but modern hardware like the AMD Ryzen™ Processor with Radeon™ Vega Graphics may lose access to important and necessary features of your motherboard. It is important that your Windows 10 PC be configured in UEFI Mode to ensure that your processor has everything it requires for optimal performance and reliability.

How do I enable UEFI Mode?

  1. You must ensure that your PC’s hard drive and operating system are configured to run in UEFI Mode. Please follow the steps in this Microsoft® video to verify or implement the correct configuration for Windows® 10.
  2. After completing the “MBR2GPT process” described in the video, restart your PC.
  3. As your PC is initially powering on, enter your UEFI menu by rapidly pressing the appropriate hotkey. Oftentimes this hotkey will be “delete” or “F2,” but your motherboard’s manufacturer can choose any key and will indicate the correct key on your display.
  4. Once inside the UEFI interface, you must locate a setting containing the text “Compatibility Support Module” or “CSM” and set this menu entry to DISABLED. More rarely, your UEFI firmware may offer a sub-menu called “Boot Mode” that will let you select “Pure UEFI” as the desired option. The exact location of these menus and settings will vary from system to system, but you are likely to find it as an option in the “Boot” menu, and it is safe to navigate between menu screens until you find the correct location. Disabling CSM will disable Legacy Mode on your motherboard and enable the full UEFI Mode that your system requires.
  5. Save your settings and exit the UEFI interface. This can often be done with the “F10” key, but there will be a menu option to save and exit as well.
  6. The PC will restart and will now be configured in UEFI mode.