Dreamcast VGA

The Dreamcast VGA Box (also known generally as a DC VGA adapter or DC VGA cable) is an accessory for Sega's Dreamcast video game console that allows it to connect to a video display such as a computer monitor or an HDTV set through a VGA port. Because the Dreamcast hardware can produce a VGA-compatible video signal natively, this connection provides improved picture quality compared to standard composite video or S-Video connections, along with support for progressive scan video.

Sega released the original VGA Box as an official accessory, but many third-party versions were also produced and sold worldwide in various form factors.

Most games for the Dreamcast are VGA-compatible, while various workarounds exist to enable VGA output from many of the games that do not feature official support.

When pins 6 and 7 on the Dreamcast's A/V out port are connected to the ground pin (such as when a VGA box is connected to the console and externally switched to VGA mode), the Dreamcast system internally switches to VGA mode, displaying a 640x480 image ( 480p progressive scan, at a standard EDTV resolution) in RGBHV at 31 kHz, which allows it to connect to a computer monitor or EDTV/HDTV set with a VGA input.

The official VGA Box consists of a rectangular black plastic case, bearing a VGA out port and a 3.5 mm minijack for stereo audio output on one side, and an A/V output jack breakout panel (S-Video, composite, and RCA stereo audio jacks) on the other, for switching output either to a typical computer monitor and speakers/headphones or to a typical TV.

Most third-party versions are functionally identical to Sega's model besides cosmetic differences, but some simplified designs lack the additional A/V breakout and output switch. These units can only be used for VGA and audio output. Some of these designs are streamlined to the point that no extra housing is required beyond the cable jacket and the connectors; such units are described generically as DC VGA cables.

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