One is a DVI-I (the one with the cross and extra 4 holes) and one is a DVI-D. DVI-I supports analogue (VGA/D-sub) cables through the use of adapter while DVI-D won't. All 4 ports are primary. The different of ports is to add more compatibility as well as for multi-monitors.
You can use any ports you want for your monitor.
February 14, 2013 9:47:20 AM
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