PCs with a DVI interface are capable of video output to an HDMI-enabled monitor. Some PCs include an HDMI interface and may also be capable of HDMI audio output, depending on specific hardware. For example, Intel's motherboard chipsets since the 945G have been capable of 8-channel LPCM output over HDMI, as well as NVIDIA’s GeForce 8200/8300 motherboard chipsets. Eight-channel LPCM audio output over HDMI with a video card was first seen with the ATI Radeon HD 4850, which was released in June 2008 and is supported by other video cards in the ATI Radeon HD 4000 series. Linux can support 8-channel LPCM audio over HDMI if the video card has the necessary hardware and supports the Advanced Linux Sound Architecture (ALSA). The ATI Radeon HD 4000 series supports ALSA. Cyberlink announced in June 2008 that they would update their PowerDVD playback software to support 192 kHz/24-bit Blu-ray Disc audio decoding in Q3-Q4 of 2008. Corel's WinDVD 9 Plus currently supports 96 kHz/24-bit Blu-ray Disc audio decoding.
Even with an HDMI output, a computer may not support HDCP, Microsoft's Protected Video Path, or Microsoft's Protected Audio Path. In the case of HDCP, there were several early graphic cards that were labelled as "HDCP-enabled" but did not actually have the necessary hardware for HDCP.[142] This included certain graphic cards based on the ATI X1600 chipset and certain models of the NVIDIA Geforce 7900 series. The first computer monitors with HDCP support started to be released in 2005, and by February 2006, a dozen different models had been released. The Protected Video Path was enabled in graphic cards that supported HDCP, since it was required for output of Blu-ray Disc video. In comparison, the Protected Audio Path was only required if a lossless audio bitstream (such as Dolby TrueHD or DTS-HD MA) was output. Uncompressed LPCM audio, however, does not require a Protected Audio Path, and software programs such as PowerDVD and WinDVD can decode Dolby TrueHD and DTS-HD MA and output it as LPCM. A limitation is that if the computer does not support a Protected Audio Path, the audio must be downsampled to 16-bit 48 kHz but can still output at up to 8 channels. No graphic cards were released in 2008 that supported the Protected Audio Path.
In June 2008, Asus announced Xonar HDAV1.3, which in December 2008 received a software update and became the first HDMI sound card that supported the Protected Audio Path and can both bitstream and decode lossless audio (Dolby TrueHD and DTS-HD MA), although bitstreaming is only available if using the ArcSoft TotalMedia Theatre software. The Xonar HDAV1.3 has an HDMI 1.3 input/output, and Asus says that it can work with most video cards on the market.
Even with an HDMI output, a computer may not support HDCP, Microsoft's Protected Video Path, or Microsoft's Protected Audio Path. In the case of HDCP, there were several early graphic cards that were labelled as "HDCP-enabled" but did not actually have the necessary hardware for HDCP.[142] This included certain graphic cards based on the ATI X1600 chipset and certain models of the NVIDIA Geforce 7900 series. The first computer monitors with HDCP support started to be released in 2005, and by February 2006, a dozen different models had been released. The Protected Video Path was enabled in graphic cards that supported HDCP, since it was required for output of Blu-ray Disc video. In comparison, the Protected Audio Path was only required if a lossless audio bitstream (such as Dolby TrueHD or DTS-HD MA) was output. Uncompressed LPCM audio, however, does not require a Protected Audio Path, and software programs such as PowerDVD and WinDVD can decode Dolby TrueHD and DTS-HD MA and output it as LPCM. A limitation is that if the computer does not support a Protected Audio Path, the audio must be downsampled to 16-bit 48 kHz but can still output at up to 8 channels. No graphic cards were released in 2008 that supported the Protected Audio Path.
In June 2008, Asus announced Xonar HDAV1.3, which in December 2008 received a software update and became the first HDMI sound card that supported the Protected Audio Path and can both bitstream and decode lossless audio (Dolby TrueHD and DTS-HD MA), although bitstreaming is only available if using the ArcSoft TotalMedia Theatre software. The Xonar HDAV1.3 has an HDMI 1.3 input/output, and Asus says that it can work with most video cards on the market.
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