Normally the BIOS should detect during POST that the PEG device is missing and drop back to the integrated graphics. That said it might not if the BIOS has been told to initialize the PEG device only.
You may need to go into the BIOS to find this option and set it to Auto or IGFX or something like that. If that's not an option you can always reset the CMOS via the jumper. Look in your motherboard manual on how this is done
Now if it never had a graphics card to begin with, that is a totally different kettle of fish.
It's obvious that it had a graphics card and it's been removed.
I would try the CMOS reset. It will set everything back to default. Hopefully this will set Boot Init Graphics back to default.