So, yesterday I was trying to install Fedora on a PC with an Nvidia graphics card, it is a bit old and it has an Intel CPU. Basically as soon as I booted the USB it went all weird like if it would be having a graphical glitch like going all rainbow in some parts and stop responding, I tried a few more times under a UEFI secure boot or something like that, and it kind of worked but only in a very small resolution and nothing had animations and so on. This was connected to a monitor via VGA.

Then I said, well, maybe it's a Fedora thing, so I installed elementaryOS and moved the PC to other place where I have another monitor that has HDMI support, I installed it while being connected to that and I had no problem, so I thought, well, it must have been a Fedora thing. I moved the PC to the other place where it was going to be used, connected it to the VGA monitor and the same glitchy thing happened, even though everything was already installed. Mind you that Windows was being used before and it was connected through that same VGA port.

What can be causing this?