HDMI mandated HDCP on the signals. If your DVI video card does not add HDCP the display may fail.
This is above and beyond the other issues you read about.
As to the pins on DVI, if you research DVI connections you soon realise why there are more pins.
Bob
I installed a DVI-to-HDMI cable between my computer and my TV, but I get no picture. Is there anything I can do to get it to work? The DVI end is called A DVI D single Link. It has 18 male pins, whereas the female connector on my Windows XP computer has quite a few more sockets than that. Thanks!

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