As Fast As Possible
AMD FreeSync synchronizes a compatible monitor’s refresh rate (Hz) with a compatible graphics card’s frame rate (FPS). As a result, all screen tearing and stuttering is eliminated within the dynamic refresh rate range of the display.
AMD Radeon FreeSync technology uses the Adaptive-Sync protocols of DisplayPort and HDMI connectors to provide a variable refresh rate which allows a monitor’s refresh rate to change dynamically and in synchronization with the graphics card.
What Is FreeSync?
AMD has worked with VESA (Video Electronics Standard Association) to add support for Adaptive Sync into the DisplayPort 1.2a standard, and later HDMI, which they then utilized for their FreeSync technology.
With AMD FreeSync, you will not get screen tearing or visual latency, you typically get from having VSYNC disabled. You won’t get the stuttering and input lag associated with VSYNC enabled either.
To take advantage of the benefits of AMD FreeSync technology, users will require a FreeSync-compatible monitor and a FreeSync-compatible AMD Radeon GPU.
What Does AMD FreeSync Do?
In order to understand how FreeSync works and what it does, you need to know how a monitor and a graphics card communicate with each other in order to create an image.
In short, the GPU renders the frames and sends them to the display which then refreshes those frames a certain number of times (60 times if it’s a 60Hz monitor, etc) to create the picture.
However, sometimes the GPU will send excess frames to the display whilst the monitor is still displaying the previous refresh cycle. This creates screen tearing (picture below).
You can get rid of screen tearing by enabling the VSYNC option in your drivers or video game settings.
VSYNC forces the GPU to wait until the monitor is ready to display the next frame thus eliminating screen tearing.
Consequently, this introduces additional input lag and if the card cannot render the frames before the next refresh occurs, it will be displayed again which creates screen stuttering.
In the end, you are choosing between screen tearing (VSYNC on) or screen stuttering and more input lag (VSYNC off).
This is where FreeSync kicks in and makes the GPU and the display work in perfect harmony within a certain refresh rate range; the width of that ranges depends on the monitor.
LFC (Low Framerate Compensation)
As long as you are within the dynamic refresh rate range of FreeSync, you will not experience screen stuttering nor tearing. If your FPS (Frames Per Second) rate dips below that range, FreeSync stops working.
The main problem here is that many FreeSync monitors have a narrow dynamic refresh rate range; for example 48-75Hz or 40-75Hz instead of 30-75Hz for monitors with a 75Hz maximum refresh rate.
Some FreeSync monitors, however, feature LFC technology which doubles the frame rate in case your FPS drops below the lower end of the range thus maintaining a smooth judder-free performance.
So, if you are looking for a FreeSync monitor, make sure to check its FreeSync range. It’s also preferable that it supports LFC.
NVIDIA G-SYNC vs AMD FreeSync
If you have an NVIDIA GPU, you will still be able to use a FreeSync monitor, but you won’t have a variable refresh rate. In that case, you will need a gaming monitor with NVIDIA’s G-SYNC technology as well as a GeForce GTX graphics card with G-SYNC support.
While G-SYNC displays have a dedicated module installed in them which significantly adds to the price of the monitor, AMD FreeSync has no extra cost. However, G-SYNC monitors also have a wider dynamic refresh rate range.
Lastly, G-SYNC is only supported when the monitor is connected via a DisplayPort whereas some FreeSync monitors work via both HDMI and DisplayPort connectors.
FreeSync 2 HDR
FreeSync 2 is the second generation of FreeSync technology which brings support for HDR PC gaming. FreeSync 2 monitors must also support LFC, have double the maximum brightness than standard monitors, and cover more than the standard sRGB color space.
FreeSync For TVs and Xbox
Unlike G-SYNC, FreeSync is also available on Xbox (Xbox One, Xbox One S, and Xbox One X) gaming consoles and certain TVs as well.
See a list of all FreeSync monitors here.
Rob is a software engineer with a Bachelor’s degree from the University of Denver. He now works full-time on writing for DisplayNinja while coding his own projects on the side.