hdmi alt mode

Many cables and adapters support Ultra HD (4K) output at up to 60 Hz for a single display. Multi‑output adapters often limit dual displays — for example, dual outputs may be limited to 4K@30Hz while single‑display mode remains 4K@60Hz.

Yes. Some cables and adapters support HDR (for example HDR10) and HDCP copy‑protection standards, and can carry multichannel audio (up to 7.1 channels) including uncompressed LPCM and common compressed formats such as DTS and Dolby Digital.

Dual‑display adapters rely on DisplayPort Alt Mode plus MST (or SST where supported) to present two HDMI outputs. The achievable resolutions and refresh rates depend on the host's DP version — for example, hosts with DP 1.4 Alt Mode may support two 4K@60Hz displays, while others may limit dual outputs to 4K@30Hz.

Typical products include USB‑C to HDMI male‑to‑male cables and adapter dongles that feature a USB‑C male plug and an HDMI female port. Listings commonly show both male‑to‑male and male‑to‑female options.

Most USB‑C HDMI Alt Mode adapters are driverless plug‑and‑play and do not require external power. They do require a host USB‑C or Thunderbolt port that supports DP Alt Mode or Thunderbolt video output.

Some multiport USB‑C HDMI hubs include a USB‑C Power Delivery passthrough port that can provide up to 100W for charging a laptop, and some hubs also include USB‑A ports that supply up to about 7.5W for peripherals.

Depending on the adapter, HDMI over Alt Mode can carry multichannel audio (including 7.1ch), uncompressed LPCM, and common compressed formats such as DTS and Dolby Digital — in some cases including high‑bit‑rate codecs like DTS‑HD Master Audio and Dolby TrueHD.