A certain vagueness (to speak politely) has been floating around for a few weeks regarding the certification of some monitors. Versions until now certified HDMI 2.0 are rebadged as HDMI 2.1. Immediately, many thought they detected a trick… But it’s not that simple.
Hold on to your seats, here we are again in a great moment of confusion and rotten marketing as our hardware industry knows how to do.
If your current interests revolve around buying a new monitor and a next-generation console, you’ve probably figured out that one of the hot topics of the moment when it comes to buying a new device is HDMI 2.1. To achieve the all-important 4K@120 Hz support (including uncompressed 10-bit color), you need more bandwidth than is possible with HDMI 2.0.
Fake HDMI 2.1?
The origin of the controversy starts with a screen from the manufacturer Xiaomi. It is a 24.5-inch display with a resolution of 1080p and a refresh rate of 240 Hz. In their specifications page, they list 2 HDMI 2.1 ports on this reference. But like a walking couch salesman’s contract, there are words in very small print and at the bottom of the spec sheet: “Due to the subdivision of HDMI certification standards, HDMI 2.1 is divided into TMDS (bandwidth is equivalent to the original HDMI 2.0 and FRL). The HDMI 2.1 interface of this product supports TMDS, the maximum supported resolution is 1920 × 1080 and the maximum refresh rate is 240 Hz.” Contacted by TFT Central, the organization in charge of HDMI certification delivered its truth and hang on, it’s a big one: just because a monitor has an HDMI 2.1 sticker doesn’t mean it supports all the HDMI 2.1 features especially those that gamers expect. Here’s an “official” summary from HDMI. org on what to consider when you have an HDMI 2.1-stamped display: 1) HDMI 2.0 no longer exists and devices should not claim v2.0 compliance as it is no longer referenced 2) HDMI 2.0 features are now a subset of 2.1 3) All new capabilities and features associated with HDMI 2.1 are optional (this includes FRL*, higher bandwidths, VRR, ALLM and everything else) 4) If a device claims to be 2.1 compliant, it must also state the features supported by the device so that there is “no confusion”
FRL stands for Fixed Rate Link and is a signaling technology supported in the HDMI 2.1 specification. FRL is required to achieve the highest uncompressed resolutions such as those above 4k60 as well as ultra high speed bandwidths up to 48 Gbps. It is also required for compressed video transport which in turn allows operation at lower data rates, for example 4k60 and ultra-high pixel rate video such as 10Kp120. VRR is a technology that can be integrated with HDMI 2.1 allowing variable frame rates from compatible graphics cards and modern game consoles. VRR can be used to reduce tearing and stuttering in variable frame rate games, and has already been implemented by Microsoft on their Xbox Series X/S consoles. Support for the PS5 is expected at some point but is currently unavailable. ALLM: Automatic Low Latency Mode is a feature that allows a display to detect a game input such as a console, and then automatically switch to a set mode that the display manufacturer has optimized for that use. Normally, this means automatically switching to a predefined “game” mode where the input lag has been reduced and many of the normal “movie” enhancement features are disabled. This is a particularly expected feature on a TV to switch from “movie” to “gaming” mode when you plug in your console for example.
HDMI 2.0 = HDMI 2.1 ???
If we understand the explanations correctly, all devices with an HDMI 2.x connection should now be labeled as HDMI 2.1, even if they only offer the capabilities of the old HDMI 2.0. generation. So a device with the “HDMI 2.1” sticker is no assurance of 4K or 120Hz… With HDMI 2.0 certification now discontinued, these are essentially 2.0 devices rebadged with the name HDM 2.1. They don’t have to offer any new features, but they are still supposed to be labeled as 2.1. This is something to consider and will probably cause a lot of problems in the coming weeks.
