Normally, HDMI is not needed for gaming purposes. Its only value for a gamer is to pass Audio to the monitor (if the monitor has speakers). But, monitor Audio is so substandard few would use it. HDMI or DVI is required to play protected content with Windows Media Center.
What's needed firstly is DVI -- it works for all purposes (including Windows Media Center). Does not transmit Audio to monitor.
Secondly, Displayport is useful for AMD Eyefinity setups (need at least one Displayport monitor). A Displayport connection will NOT display protected content in Media Center. Displayport will play Audio -- with the same issue as HDMI.
If the rumors are true, the HD7970 will be out in late January (delayed many times this year due to the manufacturer's inability to get the 28nm manufacturing process running right -- rumored no defects in the HD7970 itself). On paper HD7970 should crush GTX580 at about the same price. And, HD7970 allows for easy transition to 3 monitor Eyefinity gaming -- just plug in the next two monitors when one gets them. Something to consider. If one went that way, DVI should still be usable (two out of the three Eyefinty monitors can be DVI).
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