What is a 15 pin video connection?

A '15 pin vdieo connector' has various names, including "RGB connector, D-Sub 15, mini sub D15, mini D15 and VGA Connector" There are 3 rows of 5 pins, and they are normally blue. It was the standard output from video cards from about the late 1990s till now. While some video cards from 2002 onward only have 1 or 2 DVI (Digital Visual Interface) connectors, DVI to VGA D15 connectors are common.

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