We'll my question is if you still need a soundcard, because I wasn't sure if it's replaced to the motherboard or something.
the quality of mobo sound cards has gone up quite a bit, though my $30 asus xonar DG has a noticable quality increase on headphones, not so much my speakers though
The only time you need a dedicated soundcard is when you own good quality headphones or speakers, and you are an audiophile.
The onboard sound cards on Motherboards are usually at ~90-100 SNR (Signal to Noise Ratio) which is basically how "clear" the sound is. That's pretty good. And SNR is the stat to look at for Sound Cards as it makes the most difference, imo, to quality of sound. KHz, bits, and Channels matter, but not as much to the average user.
For comparison, most low end soundcards (the cheapest-~$80) have SNR's ranging from 90-105. Once you hit 110 SNR, the prices go from $80-$150. Then for 120 SNR, $150-$200+ (All prices are guesstimations and are accurate to within $15).
So, basically, buying anything less than $80 will likely not make much of a difference. There are rare exceptions like nna2 mentioned where his Motherboard sound card is obviously not as good as the Asus Xonar DG.
TL;DR
If you are just an average user, don't buy a Sound Card unless you are planning to spend more then $80 on one, OR your Motherboard's Sound Card is crappy, then just buy a cheap $40 one. Having premium speakers/headset would certainly be preferred if you did purchase one though.
I'd just get a FiiO DAC.