Get a home theater system lah. HTPC mah.

I'm still using an old stereo HiFi system. Most PC speaker cannot compare to it. Those high end PC speaker system will cost us more than 1k which I feel better go to those real home theater system. A lot of branded HT also not so expensive nowadays. I'll suggest you to visit both PC & Electrical shop to choose one system really meet your requirement & bugget. Different peaple will have different frequency response on their ears, best thing to do is experience it ourself to get what we really want.

It is depend on your HT and sound card. You can connect just with one stereo headphone jack from onboard sound line out to stereo RCA from HT system audio in (the easy way which I used). For 5.1 channel or digital out, you have to make sure the HT system have these input & you sound card (internal or addin) have these output. You can check on manual or back panel of the HT & sound card to confirm.