Despite what some users might think, computers and consoles are becoming increasingly intertwined. Besides sharing architectures and other hardware features, we're also seeing a certain 'transfer' of functions between both platforms. One of them is variable refresh rate. Available for a while on PC under G-Sync and FreeSync technologies, it's very likely that variable refresh rate will become a critical element for the next generation of consoles and televisions.
Now... what is refresh rate? Several colleague sites call it "update rate" or simply "refresh", but they are different expressions for the same function. In relaxed terms, refresh rate determines how fast a screen can 'update' or 'redraw' its content. And the best way to explore this is to travel back in time...
CRT Monitors: Was Analog Better?
In the old days, CRT monitors had (and still have, because I know many arcade enthusiasts who work with them daily) the virtue of presenting multiple resolutions, each with its corresponding refresh rate. For example, a 14-inch CRT could reach a ceiling of 1024x768@60Hz, but if the user dropped to 640x480, the available rates were 60, 72, and 75 Hz, or even more.
The ability to use other refresh rates was very important for one reason: increasing the rate reduced the 'flickering'. Why did so many people complain that max resolutions on CRTs gave headaches? Because the image wasn't completely 'stable', and they could perceive the monitor struggling to update its content 60 times per second (or less, if the monitor wasn't good quality).
That flickering is much more evident when you try to film a CRT monitor or TV with a camera (whether smartphone, DSLR, or similar). Both components are working fine, but the camera records the flickering, ruining the final result. Clint from the LGR channel (video below) explains wonderfully the difficulties of filming CRT monitors, especially when running DOS games, which in many cases set their own refresh rates. There are several solutions, but if you just want to film an old TV or an arcade machine, change the shutter speed to 1/60, 1/50, 1/30, or 1/25, depending on the base rate (60 or 50 Hz).
The LCD Era
With the arrival of low-cost LCD panels we received several benefits, starting with space optimization on the desk, greater energy efficiency, virtual disappearance of flicker (although technically it still exists), and simpler maintenance. However, we lost support for multiple resolutions and rates (exceptions are rare and very old).
A conventional LCD monitor has a single native resolution (any other resolution requires interpolation or 'black bars' to compensate), and supports at most one or two refresh rates. Most likely its factory default is 60 Hz, but there are also basic models at 75 Hz.
Here the problems begin. The v-sync function in a video game gives us a smoother experience, but the price is that the framerate is tied to the refresh rate. The 60 Hz becomes a 'cap' of 60 FPS that could leave unused performance on the table, and also generates lag, a fundamental factor in competitive online titles.
So why not disable v-sync? After all, it's an old trick to gain speed... but it's not without consequences. If the framerate exceeds the refresh rate, we get 'tearing' on the screen, and depending on the game engine, the absence of v-sync can cause 'stuttering'. At the end of the day, the balancing act doesn't change: smooth with lag, or fast and choppy.
High-Refresh Monitors and Variable Refresh Rates
The point is that users seem tired of making that choice, and demand the best of both worlds. The natural response from manufacturers was to start launching monitors with higher refresh rates, in the order of 144 Hz or even 240 Hz. However, that's not enough, because the only thing it does is raise the ceiling. The framerate of video games is variable, and when combining all factors (FPS, lag, stutter, tearing, and more), we need an extra element in the equation: that the refresh rate accompanies the framerate, and not the other way around.
That's where G-Sync (Nvidia) and FreeSync (AMD) technologies come in. G-Sync follows the proprietary path, while FreeSync is an open standard, but the goal is the same: break the tyranny of 60 Hz, and have the refresh rate adapt to changes in framerate. In general, these monitors have an 'adaptation range'. For example, let's take the HP OMEN 25. This 1080p monitor supports FreeSync, was validated for G-Sync, and its maximum refresh rate is 144 Hz, but its range is from 42 to 144 Hz.
And now it's time for this technology to reach consoles. Previous generations avoided the problems associated with refresh rates by applying 'hard caps' at 30 or 60 FPS, but the Xbox One X and Xbox One S already work with FreeSync. The next Xbox Series X will also be compatible with variable rates, and most likely the PlayStation 5 will follow the same path.
Traditional televisions can't fall behind either. Knowing that market a bit, I believe they will lean toward FreeSync (being an open and royalty-free technology). The future promises smoother, faster games with less lag. And it seems addictive. Everyone who tried variable refresh rates refuses to go back.
Source: Lifehacker
