This is not a warranty question, as the components are too old
I have an i5-2405S and a DH67BL. The CPU's graphics are marginal. I am not referring to performance, but integrity. Fox example, if graphics-intensive work is performed, sometimes I will see a message complaining about the graphics driver. I see the same message if I attempt to even slightly overclock the graphics to 26. It's always been this way, making me suspect that chips with lesser power were actually rejects from the i7 or i5-xxxxK lines. So I want to offload the graphics die's work onto a discrete GPU.
My question regards the BIOS option. In BIOS -> Configuration -> Video there is an option called Integrated Graphics Device. The default is Enable If Primary, but another option is Always Disable. Does it make any difference if a discrete video card is installed? I want to make sure the on-chip graphics does as little as possible.