The AVerTVHD Duet will give your existing HTPC a 'Power Boost' to higher levels of HD digital entertainment. It's designed to receive High Definition Digital TV Over-the-Air (ATSC) or Unencrypted Digital Cable (ClearQAM) signals directly to your PC! The AVerTVHD Duet is a dual digital tuner, with a single input, that adopt the brand-new PCI Express interface, which offers a stable and higher bandwidth tranmission environment than the traditional PCI bus. One of the great features about a dual tuner is that the user can watch one program, while recording another, or record two programs simultaneously!