How do sound cards affect performance?

How much do sound cards like the Audigy series affect performance in games? If I am correct, the sound cards have their own processors and they dont require the cpu to work for the sound (is that right?). In that case, how much of a performance difference would an Audigy or an Audigy 2 make in fps in games?
Thanks


Doug

p4 2.6C @ 2999 mhz
2x512mb pc3200 kingmax
ATI x800 pro
western dig. 160 gb 7200 8mb
asus p4s800

Hmm, there are no TRUE HARDWARE sound cards any more, their all hardware assisted. The Audigy can cause a HUGE performance hit compared to "no soundcard", from articles I've read up to 18%. I think the most "powerfull" solution is an "onboard" one, in the form of the nForce APU found on some Socket A boards, but even that solution carries SIGNIFICANT overhead.

People say it doesn't matter with today's CPU's. Well, if you like your P4 3.0GHz performing like a 2.2GHz, I guess it doesn't matter!

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

Actually that's a worst case scenario, I got it from a recent review of a VIA Envy with a Creative Audigy 2 comparison. Depending on the sound application, CPU usage was between 4 and 18% as I recall.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

Main difference is the sound quality comming out of your speakers/headphones.

..this is very useful and helpful place for information...