I recently installed the Creative Audigy 2 ZS Platinum Pro PCI sound card with its accompanying "breakout box"  or "I/O Hub" as they call it with a wireless remote (more for gamers).  These are quotes from a web site as to specs:

Sound Blaster® Audigy® 2 ZS delivers 24-bit ADVANCED HD™ audio quality playback with incredible 108dB SNR. It delivers the highest resolution audio playback with support for DVD-Audio at 24-bit/192kHz in stereo or 24-bit/96kHz in 5.1 surround in addition to industry leading standards, like THX®-certification and Windows Media 9: 24-bit multi-channel audio format.
SPECIFICATIONS Audio Performance
Signal-to-Noise Ratio with AES17 filter (A-Weighted)
Stereo Output 
2V Rated Output  108dB  -   1V Rated Output  102dB
Front and Rear Channels - Center, Subwoofer and Rear Center all have the same specs.
Total Harmonic Distortion + Noise at 1kHz (AES17) = 0.004% (1V, 2V Rated Output)
Frequency Response (+/-3dB, 24-bit/96kHz input ) = <10Hz to 46kHz (1V, 2V Rated Output)

High Definition Audio Quality for Playback and Recording
24-bit Digital-to-Analog conversion during playback with sampling rates of 8, 11.025, 16, 22.05, 24, 32, 44.1, 48 and 96kHz in 7.1 mode and up to 192kHz in stereo mode
24-bit Analog to Digital conversion during recording in 8, 16 or 24-bit at sampling rates of 8, 11.025, 16, 22.05, 24, 32, 44.1, 48 and 96kHz
SPDIF (Sony/Philips Digital Interface) input at up to 24-bit/ 96kHz quality
SPDIF output up to 24-bit at 48 or 96kHz
ASIO 2.0 drivers for low latency (as low as 2ms) multi-track playback and recording at 16-bit/48kHz or 24-bit/96kHz

Wave-Table Synthesis and Midi Features

Creative Hardware synthesizer (2x16 Channels) with 64-voice polyphony featuring E-MU®'s patented 8-point interpolation technology for accurate sample reproduction
Creative Software synthesizer - multi timbral wave-table (16 Channels)
2 MIDI I/O ports (2x16 channels) (gameport adapter required for MIDI I/O 2)

FireWire® (IEEE®1394) Connectivity
FireWire® (IEEE®1394) / i-Link® compatible interface with up to 400Mbps transfer rate Sound Blaster Audigy 2 ZS Platinum Pro On-Board Connectors
Line level out (Front / Side / Rear / Center / Subwoofer)
Digital CD Audio in
Aux Audio in
AD_LINK 1 and AD_LINK 2 Connectors
Power Connector
15-pin MIDI/ Joystick port extension header

Sound Blaster Audigy 2 ZS Platinum Pro External I/O Hub Front/Rear Panel Connectors
Headphone Out (1/4" Stereo Jack)
Line In 1 (1/4" Stereo Jack , shared with Microphone In with Gain Control
Line In 2 (1/4" Stereo Jack)
Line In 3 (2x RCA Jack)
Optical SPDIF In/Out
Coaxial SPDIF In/Out
Digital Out for 5.1 support (6-channel SPDIF Output to Creative digital speakers)
2x FireWire® (IEEE®1394) ports
MIDI In / Out
Infra-red Receiver
AD_LINK 1 and AD_LINK 2 connectors