How do i enable 4g decoding

Question

I dont know how to enable 4g decoding and how to navigate the bios to find it i cant find a tutorial anywhere

Answer 1

Hi Ab,

How to Enter BIOS is explained in the following:

https://www.yourwindowsguide.com/2025/08/how-to-enter-bios.html

I do not think the 4G decoding function would be in the BIOS menu. Could you please explain the problem in detail?

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Answer 2

4G decoding (often called “Above 4G Decoding” or “Above 4G MMIO”) is a motherboard/firmware feature, not a Windows setting. It is enabled or disabled only in the PC’s UEFI/BIOS setup, and the exact location and name of the option depend entirely on the motherboard/PC manufacturer. The provided information only covers how to enter firmware menus in general, not where a 4G decoding option would be.

To reach firmware/UEFI setup on a Windows 10/11 device using the documented methods:

1. Open Settings → System → Recovery (on Windows 10: Update & Security → Recovery).
2. Under Recovery options / Advanced startup, select Restart now.
3. In Windows Recovery Environment, select Troubleshoot → Advanced options → UEFI Firmware settings → Restart.
4. The device restarts into the firmware utility (often labeled UEFI or BIOS).

On some devices (especially tablets and some laptops), the firmware can also be opened by using a hardware key during power‑on, such as Volume up while pressing Power on Surface devices, or a function key like Esc, Delete, F1, F2, F10, F11, or F12 on many desktops and laptops. The exact key depends on the manufacturer.

Once in the firmware, the location and name of any 4G decoding option are not covered in the available material, so the motherboard or PC manual must be consulted for the precise steps.

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References:

• Enable Virtualization on Windows
• Boot to UEFI Mode or legacy BIOS mode