"ProXtend PCIe Sound Cards offer 100% compatibility with all major vendors, delivering performance and functionality for the most demanding entertainment and professional applications. The ProXtend PX-AU-21564 PCI Sound Card is fully compliant with PCI 1.1 base specifications. It supports 6CH DAC 5.1 surround sound output as well as full-duplex 44.1k/48khz sample rate playback while recording at 16 bits. In addition, the PX-AU-21564 supports A3D, C3DX, Direct sound 3D and EAX sound compatibility and it has a built in 32ohm earphone buffer as well as an analogue mixer for Line-In, Mic-in, Aux and CD inputs. •5.1 Stereo Sound Card •16-bit audio •Recording and playback