MR_SLINyeah this is seriously confusing but i'm totally interested in learning more as long as it is in english...
can you guys agree on something? :>
<3 ty
brand
Brands mean nothing in the audiophile world. Every company makes at least one bad product so suggestions need to go on a case by case basis.
internal v external
Unless space is limited, or you find a really good deal, external will always be better for the price simply because there is more space and the electronics are more isolated.
However, with that said, the Asus Xonar DG is probably the best bang for your buck on the cheap end ($30). Above that, external options are better choices (from strictly an audio quality position). I personally am a fan of the FiiO E17 ($140) and it has a bonus of being portable. Above that, for Americans the Schiit Magni+Modi ($200) are a great option and for slightly more (and available for the globe) is the measurement proven O2+ODAC combo ($300). Still have more to spend Mr. Moneybags? Why not check out the Diamond DAC IV+Woo Audio WA5?
However, with all the options out there you really need to ask yourself why you need a sound card in the first place. Are your headphones not sensitive, and no matter how loud you turn your computer volume they never get loud enough? Does a certain part of the headphone sound off (muddy bass, etc.) when you know that they shouldn't sound like that. If you can answer yes to this then you might need a headphone amplifier. Do you constantly hear interference when listening to music? Do you sometimes hear pops and cracks that definitely don't belong. Does the audio cut out? Then you might need a DAC.
As a heads up, some sound cards are a combination Amp+DAC (like the Xonar DG) while others can be one or the other. The same thing goes with external options.
The main reason why you might want a soundcard lies in Dolby Headphones, an effect that while I personally dislike you may prefer. Example can be found here: http://www.youtube.com/watch?feature=player_embedded&v=pVdgMQC2rYM
A very good beginners guide to all of this can be found here: http://www.reddit.com/r/headphones/comments/15wunp/guide_dacs_and_amps/