Eureka - SDVO ADD2/MEC

It took me a while but I finally discovered that there is something called SDVO ADD2/MEC which is an Intel standard for digital output from a graphics processor and is supported by their G33 and older onboard graphics chipsets (G965 etc.). I'd seen those acronyms (SDVO = Serial Digital Video Output, ADD2 = Advanced Digital Display 2nd gen, MEC = Media Expansion Card) in G33 mobo specs but didn't really figure out what it was all about.

So basically you can get a PCIe card that just adds a DVI port or even an HDMI or HDCP port to your board using the built-in graphics processor. So it occupies a graphics slot but that's fine - the question is where to get one. Searching for ADD2 and SDVO in the usual places didn't turn up any likely suppliers - most search engines think SDVO is a mistyping of SDIO...

But I have since stumbled on this list of SDVO cards from X.org which is also good because it means that the Linux people are looking at SDVO and making sure the X server supports these cards - which it apparently does. So far the only cards I've found for sale and in stock in the US are the HP and Lenovo ones which go for about $35 - a bit much for adding a single DVI port! I can see why people would want to get one on the motherboard in the first place.