Old sound card? is it still good?
 

I have a creative soundblaster audigy zs PCI sound card, would it produce better quality sound then my onboard sound (I have a MSI Z77 GD-45).

good question. I'm in to see what the people with experience have to say about it.

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while not exactly what you were looking the answer to, the Mboard you are using is realtek 892/898 based, and while very good for onboard, the creative card is somewhat better in many ways, but, it is creative as well :P