Variable refresh rate monitors

Taking the stutter out of gaming

AMD FreeSync, Nvidia G-Sync help to cut screen anomalies

Mr Shahrul Azlan is an avid gamer who is willing to spend on the best hardware to improve his gaming experience. His latest purchase is a 27-inch BenQ gaming monitor, which he bought because it supports the AMD FreeSync technology.

"I was quite excited to be one of the first few to experience AMD FreeSync on the BenQ monitor, which is supposed to enable a tear- free gaming experience," said the 25-year-old IT consultant.

He explained that he prefers first-person shooter games, such as Evolve and Left 4 Dead 2, and the monitor's high refresh rate helps with his aiming.

Avid gamers such as Mr Shahrul are being targeted by monitor manufacturers with their latest wares - gaming monitors with variable refresh rate technologies that promise to reduce stutter and eliminate screen-tearing in computer games.

AMD FreeSync and Nvidia G-Sync are the latest solutions to an age-old problem in games.

Monitors typically have a fixed refresh rate, but applications, especially games, have variable frame rates. When they are not synchronised, screen anomalies can occur and mar the viewing experience.

One such anomaly is where horizontal lines appear randomly on the screen. This is known as screen-tearing.

For older monitors without AMD FreeSync or Nvidia G-Sync, the usual solution to eliminate screen-tearing is vertical sync (v-sync).

Enabling v-sync in the graphics settings locks the frame rates at 60 frames per second (fps). Sixty hertz is also the typical refresh rate on most monitors.

Turning on v-sync prevents screen-tearing. But if your graphics card is unable to produce 60 fps for a particular scene in the game, it will cap frame rates at a fixed level, which could be 45 fps or 30 fps. This momentary change in frame rates (for example, from 60 fps to 30 fps) causes the game to stutter.

A solution was introduced by Nvidia in 2013, which is to dynamically synchronise the frame rates from the graphics card with the monitor's refresh rate. Dubbed Nvidia G-Sync, the technology involved adding a proprietary controller chip in the monitor to communicate with the graphics card.

This leads to a smooth gaming experience because the monitor is always in step with the graphics card.

AMD introduced a similar competing technology dubbed FreeSync last year. But the monitors that use FreeSync are only just reaching the market now.

The major vendors for Nvidia G-Sync and AMD FreeSync monitors are Acer, Asus and BenQ, according to IHS display analyst Hidetoshi Himuro. He said that the market share for these monitors is tiny, but growing.

This upward trend was evident at the recent IFA trade show in Berlin, which saw Acer launch four Nvidia G-Sync gaming monitors. Asus also announced a curved Nvidia G-Sync monitor at the show.

Even market leader Dell wants a piece of the gaming monitor pie. The company announced its first gaming monitor last month, a 27- inch model with Nvidia G-Sync support and a fast 144Hz refresh rate.



The first thing you need to know about these monitors is that they only work with the graphics cards they support.

All things being equal, the Nvidia G-Sync monitor will be more expensive than the AMD FreeSync model. This is because the former involves Nvidia's proprietary technology, which means more cost for monitor makers. Expect a price difference of at least $100.

On the other hand, the AMD FreeSync taps the optional adaptive sync feature present in the DisplayPort 1.2a standard. Most graphics cards now come with DisplayPort outputs.

There is no licensing cost or extra hardware involved because DisplayPort is an open industry standard.

There is another important difference between both technologies, and it has to do with the availability of graphics cards.

Currently, only a handful of the latest AMD cards (R9 and R7 series) support FreeSync. With the Nvidia G-Sync, there are more options.

This is because the controller chip for Nvidia G-Sync monitors lets it work with numerous Nvidia graphics cards, including three-year-old models. So you may not need to buy a new graphics card along with the monitor.

However, FreeSync's non-proprietary nature may be its biggest draw. Chipmaker Intel recently confirmed that it plans to support the technology in the future. While Intel's graphics chips are not powerful enough for gamers, they are found in all Intel processors, which could sway display vendors towards this open standard rather than Nvidia's closed version.

Ultimately, if you already have a decent gaming rig, you are unlikely to switch the graphics card to match your new monitor.

The good news is that there are a number of such variable refresh rate monitors from both camps.

A version of this article appeared in the print edition of The Straits Times on September 16, 2015, with the headline 'Taking the stutter out of gaming Variable refresh rate monitors'. Print Edition | Subscribe