kickstep

I'm just wondering what the general experience is with using digital surround sound and how well the amps support it and such. As a background I only have a desktop setup at home with integrated 6.1 audio with stereo SPDIF out, and analog 6.1 out. I use Logitech z-5500 speakers with 5.1 analog 2.5mm jacks and stereo SPDIF coaxial. I prefer to use digital on these speakers because there is a lot of noise, im guessing because its a moderately cheap integrated audio setup and also because digital is louder.

1. Is surround sound worth it? 5.1 or 4.1 or just screw it and go stereo?
2. How well do digial input amps work? Should i just stick with analog output from soundcard and analog amps?
3. Is it better to have a soundcard with RCA/Coaxial output instead of converting 2.5mm to it? (In the case of analog)
4. What is a good example of a digital amp?
5. I was looking at the Creative X-Fi sound cards, the more expensive ones have very good I/O options. Would anyone suggest a different sound card instead?
6. Is it easy to get a mini/micro ATX with no integrated audio or video and one PCI-E x16 slot, and at least 1 PCI slot? Any good examples with faster processor options? I'm just thinking if i end up getting a PCI sound card and avoid USB (save power consumption and less CPU usage), then i might as well get a video card too because im gonna be using up the space anyways and no point in integrated stuff to clog stuff up when i wont use it.

I think there were more questions I had but I can't think of them now. I know there are pinned posts with all sorts of digital amps and half of the things i just mentioned but there are like 100 of them and I was wondering in general how they work and what peoples experiences are with all these different parts, and any specific examples and such I don't mean to sound like i dont know anything and cant find anything myself!