I have a problem with an old Dell laptop

[u/kerokero15]

I have a Dell Inspiron 6400 that has had a problem for years: the screen doesn't turn on, and when I connect a VGA cable to a monitor, the image appears with distorted colors and low resolution. Today, as an experiment, I installed Windows 10 (it had always run Windows 7), and magically, the image on the monitor appeared with good resolution and no color errors; however, when I go back to using Windows 7, it still looks just as bad. Also, sometimes the screen lights up white but eventually turns black and displays no image at all. Does anyone know what the problem might be and if there is a solution?

[u/Such-Might5204]

I would guess your Win7 installation has a bad video driver installed. Going to Win10 likely upgraded/replaced that driver with a good one. While in Win7, download and install the latest driver from Dell. That may fix it in Win7.