How to Use BIOS to Unlock the AMD Phenom

Written by y.t. lin
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How to Use BIOS to Unlock the AMD Phenom
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All AMD Phenom II X2 and X3 processors are manufactured as X4 processors with one or two cores being locked. They are made so for a reason---to price them lower than the Phenom X4 for saving consumer's money. It is possible to unlock the cores on your Phenom II X2 (duo-core) and Phenom II X3 (triple-core) processor to convert them to the Phenom II X4 (quad-core) standard. The preferred Phenom II processors to have the cores unlocked are the Black Editions, such as the Phenom II X2 555 Black Edition or Phenom II x3 720 Black Edition. You can always overclock the Black Edition processors if the unlocking was unsuccessful.

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Things you need

  • Phenom II X2 or Phenom II X3

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  1. 1

    Start your computer. Press the F2 key before the Windows welcome screen appears to enter the BIOS of your PC. Depending on your system set-up, if F2 key does not work, try the F10, Del, or Esc key. Restart your computer before trying a new key until you get into the BIOS.

  2. 2

    Scroll and find the "Automatic Clock Calibration (ACC)" or "nVidia Core Calibration (NCC)" item on the list.

  3. 3

    Highlight the item and right-click on any blank area next to it. Choose the "Auto" option on the drop-down.

  4. 4

    Exit the BIOS by closing the window and reboot your computer.

  5. 5

    Wait for a few seconds and restart your computer, making sure everything is operating as expected.

  6. 6

    Go to the "Start" menu and click on Control Panel." Choose the "Device Manager" option.

  7. 7

    Click the "Processors" icon on the list to check if the AMD processors are now X4 designation. If you have successfully unlocked the Phenom II, the processors' information should show something like this: AMD Phenom(tm) II Quad-Core 720 Black Edition instead of AMD Phenom(tm) II Triple-Core 720 Black Edition.

  8. 8

    Check the Phenom processors if they are stable. Press simultaneously the Ctrl, Alt and Delete keys to bring up the Windows Task Manager.

  9. 9

    Click the "Performance" tab to view the CPU stats. Your Phenom processors are stable if the digits in the "Usage Percentages" pane and the graphic indicator in the "Usage History" pane are not fluctuating radically.

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