Audio controller present in SiS 630 and 730 series chipsets based on the Trident 4DWave sound card.

The main features are:

• 64-voice Polyphony 'Wavetable' sample-based Synthesizer.
• DirectSound 3D Accelerator for IID, IAD and Doppler Effects.
• Full-duplex, Independent Sample Rate Converter for Audio Recording and Playback.
• Supports 2/4/6 Speakers Output with Optional VirtualFX, VirtualAC3.
• AC'97 V2.1 Interface for External Audio Codec.
• SoundBlaster Pro/16 Compliant.
• Full Duplex VirtualPhone Speaker Phone with Modem Capable AC'97.
• V.90 Software Modem Compliant.
• Driver Support for Windows 95/98/ME, NT 4.0, Windows 2000/XP.

Unlike the later SiS 735 chipset which used the host-processed SiS 7012, the SiS 630/730 featured the fully hardware accelerated SiS 7018 core which itself is a design licensed from Trident, sold as the Trident 4DWave (the same design was also licensed by ALi for use in their 5451 chipset). The Windows 95 VxD drivers take advantage of the hardware acceleration, and there is also SoundBlaster 16 emulation for MS-DOS based games.

Unfortunately all of the hardware accelerated features only work in Windows 9x OSes using the VxD drivers, Windows 2000/XP, NT and 9x under WDM drivers only work as a basic host processed AC97 controller.