Old Monitor Not Registering New Computer

[Cloak and Dagger]

Hello, everyone. I've recently built my first computer, using the "Photon" build put out my Austin Evans. I built it following his instructions to build generally any gaming PC, and it seems to be all together. When I turn it on, it lights up and all of the fans start going. However, when I plug in the monitor (a very old Gateway analog monitor), it doesn't seem to register. The monitor requires a separate power cable, which I have plugged in, and it does turn on. I've tried it with my laptop, and it works just fine. However, it simply will not register anything from my Photon.It just gives me a black screen with a message that flashes occasionally about monitor setup, which has three options mapped to the R, G and B keys, but pressing these keys does not do anything. The keyboard is working, and lights up when plugged into the rear USB ports on the motherboard. The monitor is plugged into the blue analog monitor port linked directly into the motherboard, as the graphics card does not have a port for that format.

EDIT: I forgot to mention that my laptop is an old Toshiba Satellite E series, from 2011

 

[Cloak and Dagger]

Well, I actually found the solution for this on my own. With this setup, the monitor ports that go directly into the motherboard cannot be used. The graphics card port is digital only, but it comes with a converter to be used for analog monitors.