DisplayPort 2.1 Spec Published - All DP 2.0 Devices Compatible
DisplayPort 2.0 GPUs, displays, and other DP 2.0 certified products are compatible with DP 2.1. As for what's different with DisplayPort 2.1, from today's press release:
DisplayPort 2.1 has tightened its alignment with the USB Type-C specification as well as the USB4 PHY specification to facilitate a common PHY servicing both DisplayPort and USB4. In addition, DisplayPort 2.1 has added a new DisplayPort bandwidth management feature to enable DisplayPort tunneling to coexist with other I/O data traffic more efficiently over the USB4 link. This increased efficiency is on top of mandated support for VESA’s visually lossless Display Stream Compression (DSC) codec and VESA’s Panel Replay capability. DSC bitstream support can reduce DisplayPort transport bandwidth in excess of 67 percent without visual artifacts, while VESA’s Panel Replay capability can reduce DisplayPort tunneling packet transport bandwidth in excess of 99 percent when Panel Replay operation is taking place.
DisplayPort 2.1 has also updated the DisplayPort cable specification to provide greater robustness and enhancements to full-size and Mini DisplayPort cable configurations that enable improved connectivity and longer cable lengths (beyond two meters for DP40 cables and beyond one meter for DP80 cables) without diminishing UHBR performance. VESA certified DP40 cables support up to the UHBR10 link rate (10 Gbps), with four lanes, providing a maximum throughput of 40 Gbps, while VESA certified DP80 cables support up to the UHBR20 link rate (20 Gbps), with four lanes, providing a maximum throughput of 80 Gbps.
More details on the DisplayPort 2.1 spec via VESA.org.