Well, yeah, but that defeats the purpose - you want the IGP to be global as it's the less power-monging and heat-producing chip. If you use the NVidia one at all times, you'll be wasting power while just using the system - that's undesirable to say the least. Try resetting to Default again, or re-install with the same package (or use the update/verify tool that's built-in). I really don't know what to say, it's not *that* buggy on my end and knowing you, I doubt that you're doing anything wrong, so all I can say is "rinse and repeat"...