I believe HDMI has audio in it, HOWEVER, nobody ever uses it, they just use HDMI just like DVI (both are digital video signals, in other words... virtually no noise ever). Because who runs their audio into their video device anyways? Soon enough we'll have cheap A/V receivers that switch between HDMI, but not right now. For video, run the digital video when possible, otherwise go with component. For audio, run the digital audio (either optical or digital coax). My rule of thumb is, whenever your audio cable is going to have lots of loops or bends in it, avoid optical, otherwise... both are equally good. The real question you need to be asking yourself is what are my video sources? My dvd player (samsung dvd hd-841) has a DVI & component output, my xbox has component output & my HDTV OTA receiver supplies either DVI or component. So I use my A/V receiver to do the switching between xbox/tv through component & my dvd player shoots a DVI straight to the video device (I don't have a tv, I have a projector). If you have multiple sources that supply digital video, think about using those interfaces & finding a DVI switcher. I'm looking into a few right now.
I just bought the Mits 52525 HDTV, Yamaha HTR-5760 AV Receiver, and a set of Klipsch Synergy speakers. I also have a Sony SLV -D350P DVD/VCR. The TV has HDMI, DVI, 1394 Firewire and all the other usual connections. The receiver has S-video and Optical connections. I will be hooking up a Cable/DVR box that has HDMI along with the other S-Video connections.
My question is which of these are dedicated Video, dedicated audio, and which if any serve as both? I'm confused on the terminalogy of these connections. I'm willing to go the extra mile in cost for the best cables to match the connections but don't want to waste money. Any help would be appreciated!

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