Title has it: I swapped to the discrete GPU in the BIOS chipset settings to see if it would fix my external display problems, but apparently they were caused by the discrete GPU to begin with and now I no longer can see the screen to troubleshoot. System boots if I let it, I hear the windows login sound, and I think I am entering the BIOS by mashing the DEL key on startup, but I can’t see the BIOS or anything else now that the discrete GPU setting is selected. 

I’ve already removed the CMOS battery and reset the RAM while unplugged in hopes of resetting the BIOS to default settings, no luck. I’ve tried pressing keys by memory in the order of the BIOS menus, in case I could just change it without being able to see the screen, but no luck so far. Maybe there is a way to disconnect the discrete GPU temporarily so that the integrated one will work again?