I have a monitor that has a HDMI slot that looks like a thin socket. It also came with the cable. My graphics card is a xfx geforce 8800 GTS 640 mb and it says that it is a HD graphics card. But i cannot find where i connect the cable from the monitor into the graphics card.
I had this question a few months ago and was told that an adapter would not result in a loss of picture quality.
However, I was never given a technical response and as a result, am not completely satisfied with that answer. In fact, I kinda hope someone else chimes in on this thread with a more insightful answer.
I will say this though, one of the major differences between HDMI and DVI is that HDMI cables can carry both sound and video over, while DVI is limited to only video. As a result, one of the advanatges of a native HDMI port coupled with a graphics card with onboard sound, AKA ATI's HD 4000 series, is that its allows its user to experience sound and video with less cable work.
I might add... I too am using a DVI/HDMI adaptor. It woks great, no loss of quality. Just check that (if you're using a HDTV) one of your HDMI ports may be specifically designed for computer use as opposed to the others. Overscan and poor quality picture may result with using the wrong HDMI port. That's the way my Samsung 32" was.