“I’ve got NT 4 (you know, a “Windows” version after 98)”
Actually, Windows 98 and Windows NT 4 have nothing to do with each other. You obviously don’t know the product history of Windows NT versus Windows for DOS.
Why don’t you stop acting like you know everything and actually get an education on the subject. You’re really making an dumbass out of yourself to those who do know.
The proof that you are wrong is that you can’t give a different reason why the PC stutters with multiple videos under Windows.