QUOTE(knutinh @ Feb 22 2008, 15:12)

Ideally:
A)7.1 Analog outputs with rca and 192kHz/24bit high-grade converters. Not because anyone really needs it, but because it is technically possible, and there is content out there.
B) HDMI output, again with 8 channels of hirez LPCM (and bitstream of new BluRay/HD-DVD hirez formats as a bonus)
C) Bass management.
D) Common clock crystal for audio and video and a single HDMI connector. Meaning that perfect lip sync is guaranteed by hardware, and not by audio resampling or video framedropping.
Why is this so difficult for manufacturers, and why do they keep bugging us with "crystaliser mp3 enhancer" and all kinds of unwanted crap instead?
-k
A.
The 7.1 analog audio output via RCA jacks would take up a lot of space, and would necessitate the need for a breakout box or some sort of odd adapter. You can just buy 1/8" to RCA adapters or cables and get the same thing.
B and D.
The HDMI and common A/V clock crystal would require integrating the audio and video signals together, so the sound and graphics card would most likely have to be combined*. That is a huge change in PC architecture, unless onboard sound and video were used. Then I could see that being a possibility; a very logical one too, except that usually people don't use the speakers in their monitor or TV to play the audio, so the signal would just have to be split again, unless you fed it into an A/V receiver...except now we're talking about the HTPC market, which is a small minority of PC users, so I don't think the cost of redesigning the parts would be re-couped. But again here, you can use a DVI to HDMI adapter, and use the digital coax or toslink for audio. Sending audio over HDMI hasn't fully caught on yet anyway, IMO.
C.
As for bass management, my M-Audio Revolution 5.1's software offers it. I can set crossover frequency and speaker size, and send bass to only the sub or both the sub and main speakers.
Not all manufacturers bug you with a million useless "enhancements"...just Creative.

The only useless thing (IMO) that my Revo 5.1 has are the SRS features. No included media player, or stupid sound effects that make it sound like you're in a dungeon by screwing with the phase delays, or 5-6 convoluted options screens, etc. But even with my Revo, I could see the usefulness of one of the 2 SRS features, because it converts stereo to 5.1, which could be useful for listening to music on a 5.1 setup (the other option simulates surround sound with a stereo setup...I've listened to it, and don't care for it). I did use one feature on my old Audigy 2 ZS...the parametric EQ. It gave a lot of control over the sound, but the UI could've been better. Now that I have decent speakers, I have no need for an EQ though...but I did need the bass management (and wanted a card that didn't resample everything to 48kHz), which is why I got the M-Audio.
* They actually do sell breakout boxes that will combine a DVI video and digital coax audio signal into a combined HDMI signal...but the box I saw had an MSRP of $300, which I feel is really steep considering you don't get any extra image or audio quality; you simply need one less cable running to the TV/receiver. Here's a link to one:
http://www.gefen.com/kvm/product.jsp?prod_id=3570 I feel sorry for the people that think they need that to connect their PC to a TV or receiver.