would usb sound better than a sound card

I am experamenting with pc audio and like what i hear.i am using windows vista and a sound card with coaxial out.i am using a deqx dac-it sounds very good.i was wondering if i can get better sound using a usb dac.and it seems a lot of audiophiles are making this harder than it should.i mean using foobar with this sampling rate,and doing this and that.it seems like it is too complacated.can i please get a simple version of what sounds best.thank you.