¿Cómo elimino el Administrador de arranque de Windows de un disco duro antiguo?

How do I remove Windows Boot Manager from an old hard drive?

Access Disk Manager press Windows+X, after that click with the right mouse on the old Windows partition and delete it.

How do I disable UEFI Secure Boot?

1. Hold down the Shift key and click Restart.
2. Click Troubleshoot → Advanced options → Start-up Settings → Restart.
3. Tap the F10 key repeatedly (BIOS setup), before the “Startup Menu” opens.
4. Go to Boot Manager and disable the option Secure Boot.

You must be signed in as an administrator to delete boot loader entries on the boot options menu. Deleting the boot loader entry of an installed operating system (ex: “Windows 7”) will not uninstall the operating system. It will only remove the boot loader entry (ex: “Windows 7”) from being displayed on the boot options menu.

From here we need to delete Windows 8 from the Boot Configuration Database, on the left hand side you will see a button labeled “Edit Boot Menu” click it to get started. On the right hand side, there will be a list of all the boot loaders that your computer has been configured to use.

You can restore the Windows bootloader with a Windows 8/8.1 DVD. These instructions are inspired by Manindra Mehra’s answer, but I expanded it with full working details (verified with a Windows 8.1 DVD). Put the DVD in your optical drive and boot from it. Press a key when it displays Press any key to start from CD or DVD.

Your boot loaders are location in the EFI directory. Change to it by using the cd command and list the entries via the dir command. Your output depends on the boot loaders you have installed, here is a example with Windows and Ubuntu. Now you can delete unwanted loaders via the command Remove-Item and the parameter -Recurse.