hardware vs sw encode/decoder

[substance12]

I'm wondering how much computer resources i would free up by going with a hauppauge hardware tv tuner vs my current leadtek tv2000. I run dual monitor so when I'm playing games (currently CoH) I like to watch tv at the same time. But there is somewhat of a strain when I do that. Would I be better of investing in a hauppauge card or would the difference be minimal?

I'm running a 2.26ghz p4 512 dual config 400sc; 9500 pro.