How to know if the computer is using EFI/UEFI or BIOS firmware interface
To determine whether your computer system is using BIOS or EFI/UEFI please follow the steps below:
1. Login to Windows.
2. Go to Start ► Computer
3. Navigate to C:\Windows\Panther\setupact.log
4. Open setupact.log
5. search for the following string:
'Callback_BootEnvironmentDetect: Detected boot environment:'
It should tell us the boot environment: BIOS or UEFI in the following format:
Code:Callback_BootEnvironmentDetect: Detected boot environment: BIOS
OR
Code:Callback_BootEnvironmentDetect: Detected boot environment: UEFI