If nothing is plugged into that old Intel 3000, maybe you can disable it in Device Manager.
Then update the drivers for your Nvidia GeForce card.
That’s a very old computer and the GeForce has less than the minimum recommended amount of VRAM for V6.
I suspect this would have worked pretty well for Rhino V6.
If you’re serious about V6, you need a new computer that meets https://www.rhino3d.com/6/system_requirements.
Sorry