My son gave me this machine because it ran "upgraded" Windows 10 like a lame sloth. I've put Kubuntu and MX Linux on it and they both ran well, and we've used it to teach class over the internet. But I can't figure out how to adjust the screen brightness. There's a conflict between the brightness and screen ext/int functions; they both run at once. I've fooled with the keyboard settings endlessly, and fruitlessly. It's the blue "Fn" button that doesn't have the right driver, or something. Fn + any of the other F buttons doesn't work either.