[Perndog]

EDIT: Pardon me. Internal digital input is what lets you hook your CD-ROM straight to the sound card for playing CDs. Most sound cards have it; this one doesn't.

What makes the Audigy Platinum shine (and why I bought it) is its connectivity. The sound card you're looking at has a digital out, a mic in, a 1/8" line in, and speaker outs. The Audigy 2 ZS Platinum has (on the card) all of the above plus a Firewire port and an additional front panel that includes: a 1/4" headphone out, a 1/4" line/mic in, optical AND coax SPDIF I/O, MIDI I/O, digital I/O, another Firewire port, another digital out, a 15-pin joystick port, and a remote control receiver - the Platinum Pro adds a stereo RCA line in.

I'm not sure about the sound quality difference between the audigy and the other brands. I have a first-generation audigy and it sounds fantastic to me; at this point I think the differences are starting to be nominal. I say buy the cheapest competing sound card and spend the extra money on some speakers that will let the sound card do its job right.