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      BIOS Update for Windows 8.1 (32-bit, 64-bit) - Lenovo G400, G500

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      Operating System
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      BIOS Update
      4.42 MB
      Windows 8.1 (32-bit)
      Windows 8.1 (64-bit)
      README of BIOS Update
      4 KB
      Windows 8.1 (32-bit)
      Windows 8.1 (64-bit)

      Supported Laptop Systems

      • Lenovo G400, G500

      Supported Operating Systems

      • Microsoft Windows 8.1 (32-bit, 64-bit)

      Important Information

      • BIOS, abbreviation of Basic Input/Output System, is integrated in ROM chip on main board, which contains the basic input/output program, system configuration information, system startup self-check and pre-setup programs. BIOS provides most basic low-level hardware operations; it is the connection between software and hardware, and interfacing window of hardware and operating system.

        Note: Make note of any settings you have changed in the BIOS Configuration Utility. These settings may have to be re-entered after updating the BIOS.

        Attention: Do not power off or restart your computer during the BIOS flashing process, which will cause serious damage and improper functioning of your computer.

      Summary of Changes

      Latest Version BIOS fixed all merged issues from previous.

      Version 78CN25WW(V2.03)

      BIOS Notification:


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      1. Modify to support Cbt RTL8723BE WiFi 1x1 BGN+BT4.0.

      EC Notification:


      1. N/A


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      Downloading the package

      1. Click the file link to download the file from the web page.
      2. When prompted, select a drive and directory in which to save the downloaded file.

      Install the package in Windows

      1. Locate the file 78cn25ww.exe that has been downloaded.
      2. Double click the 78cn25ww.exe icon.
      3. Click install
      4. Click flash bios
      5. Press Enter to start flashing. During the process, you are advised not to turn off the computer.
      6. When the update finishes, the computer will automatically reboot for the changes to take effect.
      7. If the hot key not work without Fn key after flash BIOS, this SOP describes how to enable hot key mode
      • Step 1: Press power button to boot, then press F2 key enter BIOS setup.
      • Step 2: Select sub menu to Configuration.
      • Step 3: Select to Hotkey Mode item and then press enter.
      • Step 4: Select Enabled then press enter.
      • Step 5: Press F10 save and exit, then select Yes then press enter.

      • Alias ID:
      • Document ID:DS036474
      • Last Updated :31 Aug 2016
      • © 2015 Lenovo