Answer:
The onboard video card should be disabled in the BIOS. After you disable the onboard video card in the BIOS, it will no longer function.
Step-by-step explanation:
Since in the question a user wants to upgrade for new graphics application and also the computer involves the onboard video card and a new video card is installed in the computer now you want to disabled it
So this can be done in the BIOS i.e basic input output system which is to be used for rebooting the computer system
And after disabled it, you cannot used.