VRR: what it is and how to take advantage of the Variable Refresh Rate on PS5, Xbox Series X | S and PC

VRR

Graphic innovation considers video games as a real test of real-time rendering of an image on the screen. Screens increase in resolution and refresh rate and it really takes a lot of computing power to get a game engine to print images with the required detail and speed into a two-dimensional color matrix. Not always a console or a PC are able to develop a frame for each slot made available by the screen that reproduces them. Especially in recent years when monitors have panels that reach and exceed the 300 Hz wall and that are potentially capable of reproducing up to 300 different images in just one second.

The acronym VRR , or Variable Refresh Rate, indicates all those technologies that allow a screen to adjust the reproduction speed of the frames to that coming from the graphics card. The need for such a stratagem arises precisely in function of the problems that afflict the gaming experience when the frequencies between monitor and GPU do not coincide such as tearing, judder and lag. Although VRR indicates a set of different technologies, today the term is mostly associated with the specification related to HDMI and the TV domain, which is sometimes also called "Adaptive Sync". The VRR has risen to the headlines because it has only recently entered the living room of many gamers with Xbox Series X | S and PS5, despite having been active in the PC field for several years now in different forms. The impact of VRR in the console environment is significant, because it gives a way to improve the visual experience in the round, without requiring additional computing power. The benefit is consistent in particular in eliminating visual artifacts when the framerate is not stable and therefore in providing a more fluid and homogeneous experience to the player.

To take advantage of VRR you need a compatible monitor or TV and a GPU capable of supporting this functionality. The latest generations of AMD and NVIDIA graphics cards fully fall into this category, as does the plethora of G-Sync or Freesync monitors. For consoles and TVs, however, the situation is slightly different.

Xbox has made VRR available with the previous mid gen, that is Xbox One S and One X, and immediately ferried it to Series S and Series X, thanks to the compatibility provided by AMD's RDNA2 GPUs. Freesync technology is in fact based on Adaptive Sync and therefore compatibility with one almost naturally means compatibility with the other. PlayStation, on the other hand, while basing its system on a similar hardware architecture, has only unlocked this feature for a few days and only as Adaptive Sync, not FreeSync.

Below we will try to explain in great detail what VRR is. and how to take advantage of the Variable Refresh Rate on PS5, Xbox Series X | S and PC.

What is VRR, how does it work?

An HDMI 2.1a VRR socket stands for of Variable Refresh Rate. It is not such a recent technology: the first implementation of G-Sync dates back to 2013, but its implementation in consoles and televisions is. The reason lies in the definition of the HDMI 2.1a specification. Behind the HDMI standard there are actually many specifications and versions of this format that define and update the data exchange protocol between source and panel. The 2.1, defined in 2017, brings many new features, the most important being the increased bandwidth at 48 Gbps (from the 18 Gbps of 2.0) sufficient to support a 4K 120Hz or 8k 60Hz video signal.

But there are many others. Specification 2.1a brings with it support for Variable Refresh Rate, Auto Low Latency Mode and Quick Frame Transport. All three define a type of interaction that seeks to eliminate visual artifacts and minimize input lag: increasingly fundamental elements for the visual experience of gamers.

The latest generation consoles are all certified to the full HDMI 2.1a specification, but the application or not of the entire feature set must be enabled before it can be exploited by the user. To be precise, it must be written that VRR was actually supported already starting from the HDMI 2.0 specification, although it was not mandatory and was obviously limited to 4k 60Hz resolution. This is why Xbox One X and Xbox One S already support it.

PS5 recently enabled VRR Going back to VRR, the execution theory is quite simple. Imagine the data stream coming from a console as a sequence of images and the receiving stream of a monitor as a series of slots in which to insert these frames. The monitor has as many slots per second as those indicated by its refresh rate, calculated in Hz, or the inverse of the time measured in seconds, which also represents how many times the pixel matrix of the monitor is able to change from one image to another. 'other.

If each frame had an absolute rendering time identical to the previous one, it would be enough to synchronize the incoming stream with that of the monitor and we would have for each single image a representation on the monitor, without artifacts, but it is not always like this. A particularly resource-demanding scene can slow down the render time of a frame and in that case the computer would not be able to fill the slot provided by the monitor. A scene with too many frames could cause more than a single frame to be inserted into the monitor's playback loop.

Without VRR the monitor can play the same frame in memory, waiting for the graphics card to have access to it. a new frame, or he can insert the part of the frame he has processed, covering the previous one only partially, and end it in the next one.

Depending on the specific situation and the behavior of the monitor, 3 types of visual artifacts are created: tearing, judder and lag.

Tearing is the phenomenon that occurs when the monitor plays simultaneously a part of the new frame and a part of the old. It occurs when the computer is too slow or too fast to create a new frame and the graphics card is not given additional instructions on how to delay the signal of the various frames to match the frequency of the monitor. It is very easily identified as a sort of image broken into 2 parts, usually in the central area of ​​the monitor.

Tearing Judder is instead the phenomenon that occurs when synchronization algorithms are applied to the graphics card, but the framerate of the video is lower than the frequency of the monitor and is not a maximum common divisor. Think of a 24 fps signal on a 60 Hz monitor. Dividing 60 and 24 gives 2.5. Some frames are played the same as the previous ones twice, others three. This creates an uneven trend of the video whose reproduction goes to "hiccups".

Input lag is a phenomenon that is always present and defines the time that passes from activating a command to seeing its reaction on screen. Low input lag values ​​improve the gaming experience and this is why frame synchronization software technologies such as V-Sync have never been able to permanently solve the aforementioned problems. They put the GPU on hold until the monitor is able to receive a new clean frame and introduce an inevitable lag, both due to the calculation and the intrinsic waiting on which this method is based.

Spider -Man is one of the last games to have introduced VRR. We do not insert in the visual artifacts those created by the interpolation of the frames, that is the set of techniques that simulate intermediate frames if there is one missing. They generate an input lag of even hundreds of milliseconds unnecessary and are deactivated by selecting Game mode or if the screen recognizes that it is connected to a console.

With VRR enabled, the monitor waits for the moment to receive the new one. frame by the GPU and then reproduce it. In this way the GPU works at its maximum performance, without waiting or limitations. The monitor no longer receives the frames based on the time partialization according to the set frequency, but adapts it to that of the incoming frames. In this way the images are much smoother and the artifacts disappeared.

The only limit of VRR lies in the operating range of this technology which often goes from 30 Hz to 120 Hz (OLEDs usually start at 40 Hz). In this case, when the FPS falls below the threshold there is a technical limitation of the panel that does not allow you to slow down the playback to that point. Think for example of the unstable 30 fps to which some games that have a particularly heavy graphics system are anchored. In this case, some panels use LFC, Low Frame Compensation, which doubles the input frames to then activate the VRR, but this technology is not part of the application of VRR and can only be the prerogative of some models. Under specific conditions of use, among other things, this feature introduces a lot of input lag.

VRR on XBox and PlayStation

Xbox Series X Microsoft's vision for its Xbox as Universal gaming console has simplified the approach to many technologies compared to Sony, which has always seen PlayStation as the typical living room entertainment box. Support for "monitor" resolutions such as QHD or Freesync and VRR at Microsoft took place a good half-generation ahead of PlayStation, which with PS5 still had to wait for a good year and a half after launch.

In partial defense of Sony we can confirm that only in the last year VRR has really taken hold in the most mass range of televisions and for Sony so far there was no need to chase this technology, given that users with Freesync and G-Sync monitors that support VRR didn't justify it even in the days of PS4 Pro.

Beyond that many 2021 TVs, despite adhering to the HDMI 2.1a specification for marketing and that potentially would have supported post-launch VRR, are only unlocking its features in recent months thanks to the release of ad hoc firmware.

Not all TVs support VRR Among consoles, VRR is now available on Xbox One S, Xbox One X, Xb ox Series S, Xbox Series X and PS5.

Nintendo Switch does not support VRR. The original SoC of the Nintendo console, the Tegra X1 + while coming to support HDMI 2.0 specifications, including HDR, was originally engineered in conjunction with a dock with HDMI 1.4 specifications and will never be able to support VRR. The new OLED version, on the other hand, while using a dock with HDMI 2.0, is based on an outdated chip that would need a small refresh to be able to adopt the VRR functionality and we doubt that this will happen.

How to activate VRR on PlayStation 5

PS5 DualSense Going to the Settings menu, continue until you find Screen and Video and then Video Output. If you connect PS5 to a monitor that supports VRR you will find the setting of the same name. The function is automatically activated for all games that support it. If you want to activate it for all games without distinction from the support guaranteed by Sony, you must select the following checkbox.

How to activate VRR on Xbox

Xbox Series X and S To activate the Variable Refresh Rate on Xbox just go to Settings and then Video Mode. From here, look for the checkbox to Allow variable refresh rate. At this point the Microsoft console checks compatibility with FreeSync or Adaptive Sync technology and will activate automatically if one of the two is available.

Which TVs and monitors are compatible with VRR?

More and more panels support VRR VRR is a technology that involves communication between monitor and console, so they must both be compatible with it in order to function correctly. Below you will find the list of compatible and non-compatible TVs with PS5 and Xbox Series X | S; the number rises daily because it also includes the whole universe of models compatible with Freesync.

We want to leave you a small suggestion if this list is no longer updated with new models or new firmware. VRR is integrated into the HDMI 2.1a specification with Adaptive Sync, but the TV may not necessarily adhere to the HDMI 2.1a specification to support VRR. Pay attention to this aspect. There are a number of models that support VRR but do not have 4K 120 Hz panels. It does not mean that all TVs that support VRR have "gaming friendly" input lag, this mainly depends on the hardware used and the management chip. panel, because a minimum of image processing is essential even for a simple color conversion.

VRR management depends a lot on the type of TV panel: LED, OLED and VA can have a slightly different rendering . OLEDs for example, despite being excellent for gaming due to their reduced input lag and black rendering, cannot keep the pixels on for too long and in the case of low framerates this generates visual artifacts at the dynamic curve. This is also why OLEDs do not support VRR below 40Hz, while LEDs and VAs can easily go as high as 30Hz.

So you may not get the benefits of VRR equally on all monitors and in all possible situations.

VRR in compatible games and forced mode

Marvel's Spider-Man 2 In video games the Variable Refresh Rate makes a greater contribution than it is easy to imagine. As PC gamers know, it improves the gaming experience in many ways, while not giving FPS or changing the experience. Games are smoother, even when FPS isn't quite stable, and are much more responsive due to the reduced input lag. All this while removing the phenomena of tearing and juddering.

PS5: support for VRR arrives this week, list of supported games - Nerd4.life
PS5 makes a distinction in the settings between games that support VRR following a patch and those that do not, but can still forcefully adjust to it. A bit like the boost mode did in the past on PS4 Pro.

Supported games have dedicated information that serves to define the typical behavior that the monitor should have with a game, based on the framerate that set of games. 'settings want to achieve. This becomes especially important when it comes to modes that travel around the unstable 30 FPS and could therefore swing between a VRR on and off situation.

Setting it in a forced manner should not penalize the experience, unless you are in a situation that straddles the minimum FPS limit for its activation. We advise you to keep it activated and deactivate it only in case of problems that given the type of technology should not be many: at the limit you will experience black screens or a clearly unbalanced color rendering. You can rest assured because in no case will enabling the force option to damage your PS5 or the monitor / TV used.

Have you noticed any errors?