RE: How to setup Dual Monitors
The 780 MT does allow full size video cards. The 780 DT/SFF do not. Do you have the one on the far right?
The onboard GPU is enabled with the add in DVI card J4571. So you could use both.
The onboard GPU is disabled when a PCIe x16 video card is installed on the motherboard.
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Run the PC pre-Windows diagnostics
Where do I find my Dell PC Service Tag or Express service code?
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