G-sync and FreeSync monitors provide hardware solutions to a persistent display problem: screen tearing. The competition between NVIDIA and AMD in providing a solution to screen tearing has given consumers a variety of options from both a cost and performance standpoint.
G-sync monitors use proprietary technologies by incorporating a chip or module inside the dedicated G-sync monitors that allows the monitor and GPU to communicate and synchronize frame rates and reduce or eliminate screen tearing. FreeSync, on the other hand, does not use any additional technologies and simply employs the open standard of adaptive synchronization technology present in DisplayPort connections to reduce or eliminate screen tearing.
This article will explain the nature of screen tearing and the V-sync software solution to address the display problem. It will then introduce NVIDIA and AMD's hardware solutions through G-sync and FreeSync monitors, respectively.
Screen Tearing
In a computer system, the graphics processor unit (GPU) is responsible for producing images on the computer screen. Depending on the GPU's capabilities, it can produce a certain number of frames per second depending on the application.
The computer monitor is the computer hardware that displays the information that the GPU sends. The panel technology used in the monitor will determine the frequency of transition per image or refresh rate of the monitor.
The disparity between the GPU's FPS output and the monitor's refresh rate can cause erratic images; This is called screen tearing.
Screen tearing can also occur due to sudden drops or spikes in frame rate from the GPU where-in the computer monitor cannot keep up due to hardware limitations.
V-Sync
V-sync or vertical sync is a software tool that allows the GPU to maintain a certain level of frame rate transmission to the monitor depending on the monitor's specifications and capabilities.
It prevents issues like screen tearing but can also cause input latencies. Usually, input latencies occur in fast-paced games as the V-sync features cap the game's FPS to suit the capabilities of the monitor.
The primary problem with V-sync is that it prevents the GPU from performing at the peak of its capabilities and accustoms performance based on the capabilities of the bottleneck, the monitor.
The input lag and the dip in performance may also become apparent and negatively affects in-game response time.
Introduction to FreeSync and G-sync
To provide a solution to screen tearing without limiting the capabilities of the GPU and without reducing in-game performance, NVIDIA and AMD introduced G-sync and FreeSync monitors respectively as hardware solution.
Both G-sync and FreeSync work similarly to V-sync. However, both are hardware innovations that use similar adaptive synchronization technology to control refresh rate depending on the GPU's frame rate transmission.
The adaptive synchronization technology is a built-in feature of the DisplayPort connection, which Freesync takes advantage of to deliver the technology without requiring additional hardware. Soon after, the adaptive synchronization technology also became available through HDMI connection.
FreeSync
FreeSync uses the open standard on adaptive synchronization technology for LCD monitors using the built-in protocol in DisplayPort 1.2a. It is currently not compatible with legacy connections such as VGA and DVI.
To use the adaptive synchronization technology in FreeSync monitors, the AMD GPU must also support adaptive synchronization technology. Older graphics cards are therefore unable to use the technology.
Freesync provides an alternative to NVIDIA's G-sync by using an open standard that does not require the use of additional hardware. It is also cheaper to buy a FreeSync monitor than a G-sync monitor since the latter uses proprietary means to provide a hardware solution to screen tearing.
While G-sync has been present longer, Freesync has become a direct competitor to G-sync for addressing screen tearing issues. It uses price and compatibility as its general selling point.
Freesync 2 is the the latest iteration. The new version provides HDR support, the capability to switch between standard dynamic resolution (SDR) and high dynamic resolution (HDR), and low framerate compensation (LFC).
LFC addresses the stuttering issues found in previous FreeSync monitors where-in framerate dips beyond the threshold supported by the FreeSync technology.
G-Sync
NVIDIA's G-sync monitors use proprietary means rather than open standards by inserting a chip/module inside the computer monitor to communicate with the GPU and prevent fluctuation of FPS and screen tearing.
This solves the previous issue where the monitor only receives data from the GPU irrespective of the differences in performance and capabilities of the two hardware.
G-sync monitors require dedicated graphics cards that support G-sync technology and also require the user to connect the GPU to the monitor using a DisplayPort connection.
The G-sync module inside the monitor is responsible for the smooth gaming experience with no tear, flicker, or artifacts. It synchronizes the performance of the GPU and the monitor by controlling the vertical blanking interval (VBI) or the transition of the monitor towards subsequent frames.
NVIDIA also works with various companies responsible for manufacturing monitor components to provide the best materials for G-sync monitors in terms of supporting G-sync standard refresh rates, response times, flicker properties, and visual quality.
The level of quality control and assurance that NVIDIA puts in G-sync monitors helps to explain why many people feel G-sync monitors are superior to FreeSync and it justifies why G-sync monitors are more expensive.
G-sync Ultimate is an upgraded/refined version and offers HDR and 4K resolution support. It also supports refresh rate overclocking which produces very minimal motion blur ideal for competitive e-sports titles. It also has LFC to remedy the ghosting issues or the retaining of faint images of previous frames on present frames.
G-Sync-Compatible FreeSync Monitors
FreeSync and G-sync monitor technologies are known to be incompatible. FreeSync monitors cannot use the G-sync support in NVIDIA video cards while AMD video cards cannot use G-sync technologies in G-sync monitors.
Recently, however, NVIDIA announced that the G-sync features in modern NVIDIA graphics cards can now support FreeSync monitors. However, upon examination of over 400 FreeSync monitors, only 12 brands and models were released to work with G-sync technologies.
People who are tight on budget and cannot afford to buy a dedicated G-sync monitor can now opt to buy NVIDIA's recommended G-sync-compatible FreeSync monitors.
G-sync should automatically activate once it recognizes a compatible monitor. However, this will often require updating the G-sync graphics card to version 417.16 onwards.
Final Thoughts
Screen tearing has been a persistent issue as monitor technology development has lagged behind that of graphic cards.
G-sync and FreeSync monitors are ideal solutions to reduce the bottleneck through hardware rather than software changes targeted at the monitors, which are often the cause of the bottleneck, rather than the graphics cards. This allows the computer to harness the full potential of the graphics card in delivering outstanding graphics at high frame rates.