How can I set up my PC so that it boots to the VGA/integrated graphics?
I am having no problems until I hookup the GPU. I know this because my first rig is attached to a tv so I use the HDMI through the GPU but my second rig is attached to a VGA monitor. I don't have the ability to hook it up through the GPU because I do not have a compatible display.
You could get an adapter that would allow you to connect a VGA display to a graphics card.
Alternatively, if your rig runs Windows, switching your rig to use the iGPU for display should be easy; just go into the BIOS, set the rig to default to the integrated graphics, connect to the integrated graphics, and you should be good.
If your rig runs Linux, I'd recommend getting an adapter instead of trying to run drivers for both the integrated graphics and the discrete GPUs. It's possible, but a real pain.
If you haven't setup your second rig yet, use the TV with HDMI until you've finished setting it up, then make the necessary changes to use the iGPU with the other monitor.
