Who says people don't use the discrete analog ins? Lots of people do. That's the best way to go for gaming. The only reason why not to is because it's inconvenient- as you can see receivers only have one set of them and they are usually occupied by something else (like a Blu-Ray player, etc, etc). If you want to get a little better you might consider a Audigy so you have EAX-HD/OPENAL hardware support, otherwise forget it, you have a perfectly suitably gaming setup built in.
My motherboard has the same soundchip. Just go to Realtek, d/l the latest drivers and you'll be all set. There is no quality loss using analog, in fact it's superior. The people buying the DTS soundcards want better sound for home theater. They are not gaming cards.
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