The HDMI Forum confirmed the development of the next-generation HDMI standard with increased bandwidth. According to various media reports, including Videocardz and Dday, the press release from HDMI Forum indicates the possibility of new cables or refinement of existing specifications. Moreover, it could mean we will have new HDMI 2.2 specs. The current HDMI 2.1 specifications, established in 2017, provide bandwidth up to 48 Gbps and support native non-DSC configurations for 4K at 144 Hz and 8K at 30 Hz. When combined with Display Stream Compression (DSC) technology, the current standard can handle up to 10K at 120 Hz. A bandwidth increase could enable higher resolutions and refresh rates without DSC compression.

This development of new HDMI specifications is due to the emergence of other display interface standards such as DisplayPort 2.1, which offers up to 80 Gbps over UHBR20. AMD's Radeon RX 7000 series and Intel's recently launched Arc Battlemage GPUs support UHBR 13.5 while the Radeon PRO supports UHBR20. The HDMI Forum is scheduled to release these new specifications on January 6th, one day before the official CES 2025 opening event on January 7th. With the launch of NVIDIA's GeForce RTX 50 and AMD's Radeon RX 8000 series at CES 2025, it would be interesting to see if the latest graphics cards will support the HDMI 2.2 specs.

AMD recently tried to add support for key HDMI 2.1 features like 4K@120 Hz and 5K@240 Hz to their open-source Linux graphics driver called AMDGPU. They invested engineering resources over several months to prototype the necessary code internally before publishing. The goal was to showcase HDMI 2.1 capabilities and get the implementation approved by the HDMI Forum. Unfortunately, the Forum ultimately rejected AMD's request, blocking Linux users of new AMD Radeon GPUs from utilizing those cutting-edge display features over HDMI. In comments, AMD stated: "The HDMI Forum has rejected our proposal unfortunately. At this time an open source HDMI 2.1 implementation is not possible without violating HDMI Forum requirements." This outcome comes as a major disappointment given the time and effort AMD expended aiming to satisfy the Forum's guidelines. The months of work now feel wasted with this outright rejection. As reasoning, the HDMI Forum cited legal and compliance rules around not enabling open-source HDMI 2.1 code.

Legal issues and compliance are major problems for open-source HDMI developers, as HDMI Forum has decided to make the HDMI specification private in 2021. This directly translates into the newest open-source driver developments, where the latest features will probably remain behind a closed-source binary. Consequently, AMD is advising Linux gamers to use DisplayPort if they want access to features like 4K 120 Hz gaming. Meanwhile, Windows AMD users still get full HDMI 2.1 capabilities. This dichotomy spotlights the ongoing obstacles around open-source driver development. The rejection also strains the AMD - HDMI Forum relationship. AMD hoped spearheading open-source HDMI 2.1 drivers would position them as leaders in the open-source community. Instead, their flexibility plea was denied by the rigid HDMI Forum requirements. Ultimately, whether Linux-based AMD owners can ever utilize next-gen HDMI 2.1 displays fully remains to be determined. For now, AMD continues pushing open-source as the best approach, while the HDMI Forum refuses to budge on compliance demands. Both sides seem firmly entrenched, leaving consumers caught in the middle.