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I have a recent asus motherboard with an i7 processor and i've got a nvidia 670gtx connected to it.
For various reasons/experimentation purposes i'd like to connect my monitor to the intergrated graphics adapter rather than my gtx 670 card.
If i connect it to the motherboard's DVI connector the screen does not display any image on POST, nor when i'm actually in my OS, if i move the connector to the GTX card i get an image however.
Why is this happening? how can i use the intergrated graphics port to connect my monitor? (it must not involve disconnecting the GTX card)