your onboard sound might be just as good, im on an Asus A8N SLI Premium Mobo, and am getting rid of my 3-4 year old Soundblaster Live 5.1 Digital, and using the onboard Sound (Realtek), and i can't even tell the difference between the quality, if you are not fuss about listening to high quality music or playing games with high quality sound, onboard might be ok, but it depends on the type of motherboard you got, but my onboard sound is good enough for me, music and gaming, i play CSS using onboard sound, no difference to my SB Live 5.1 in my opinion, although it's 3-4 years old.