clmlbx is correct! for your usage-needs, you would not want to unnecessarily spend on a costly sound card. i could've suggested to you the asus xonar dg sound card, which retails for close to INR 1.6k, but then you probably won't be using headphones much (since you haven't mentioned it), and would game too just occasionally, so even this cheap sound card may not be utilised well by you (since it comes with a dedicated headphone amp and gaming audio-engine....its a VFM buy).
remember, atleast in case of audio/video, you should first choose a good source, then choose good medium (ie, speakers), because if you first choose good speakers, and neglect a good source, what you are going to listen is what will be fed to it, ie, garbage in --> garbage out, and then you may blame the speakers themselves to be useless, wherein the source really is the culprit; but if you go by the correct way mentioned, then its the other way round, because the hallmark of a good audio/video medium/device is, it should output the source signal with least fiddling done by its own. processing is the job of the source, and should be left to it.
- if you first get a good (processing) source, and THEN get good speakers, then you get a good output.
- if you neglect a good source, and buy good speakers, then you get mediocre output (for a mediocre source).
- if you get a good source, but get bad speakers, you get bad output (since bad speakers can't do justice to the capabilities of the good source).
this is not to say that your current source (onboard sound) is bad. in fact, it is just apt in the current scenario!
so having a set of budget speakers (you could go ahead with mentioning your budget now....we could suggest you some models) for your kind of usage would be recommended. but if you would like to still insist, xonar dg could be a decent choice for a sound card for you. let us know if you would like to discuss which speakers to select.
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