So, you have just gotten a variable refresh rate gaming monitor, paired it with a compatible graphics card, and find that turning on FreeSync/G-SYNC Compatible causes horrible brightness flicker?
There are several things you can try to prevent or reduce flicker.
FreeSync brightness flicker is most common on VA panels with high refresh rates developed by Samsung, but it can also affect displays based on other panel technologies such as IPS and TN.
The problem will not necessarily be present in every game. Some games may experience unbearable brightness flicker. In others, it may work flawlessly, and in some, only on loading screens or in game menus.
Also, keep in mind that one unit of a particular monitor may have this problem, but another unit of the same monitor model may work fine!
What is behind all this is a bit of a mystery and AMD/NVIDIA has not had an official answer, but we do know that some monitors are just more prone to this problem.
So, why is this happening and what can you do to prevent it?
Reducing brightness flicker in AMD
Let us say you have a 144Hz VA gaming monitor whose brightness flickers in some of your games.
There are two main causes of brightness flicker: LFC and frequent FPS fluctuations.
If you are gaming monitor has a variable refresh rate range of 48-144Hz, it will trigger LFC (Low Frame Rate Compensation) as soon as your frame rate (FPS) reaches 47 FPS or less if, you are using an AMD graphics card.
LFC multiplies your frame rate to eliminate gaps even when your FPS falls below the monitor’s VRR range. For example, at 47 frames per second, it triples to 141 Hz.
So, let us say one second you have 48 FPS and 48 Hz, and then the next second your FPS drops to 47 FPS and the refresh rate goes up to 141 Hz.
As the monitor gets brighter at a higher refresh rate, the brightness fluctuates.
If the FPS is consistently around 48 FPS, the LFC will turn on and off quickly, causing the brightness to flicker.
A simple solution is to reduce the image settings to maintain a higher frame rate.
Alternatively, you can use the CRU (Custom Resolution Utility) to increase the VRR range.
As with overclocking, increasing the VRR range will vary from monitor to monitor.
Thus, you can increase the VRR range to 30-144 Hz on one monitor, while another device of the same monitor may not even go to 47-144 Hz.
In the latter case, you can try reducing the range instead so the LFC does not kick in, or you can turn off the LFC completely by reducing the range to 73-144 Hz.
LFC with AMD cards works only if the lower limit of VRR range is at least 2 times higher than the maximum refresh rate. For example, a VRR range of 30-60Hz means LFC works, but with 31-60Hz, there is no LFC support.
By disabling LFC, you have to use VSYNC to get rid of screen tearing at lower frame rates, but you can still use FreeSync at higher frame rates without problems.
FreeSync brightness flicker can also occur when FPS fluctuates, even if it does not approach the LFC threshold. This mostly happens in poorly optimized games where your FPS depends on many factors.
The only way to reduce brightness flicker is to limit your FPS in that game to whatever frame rate you can maintain at all times.
Reducing flicker on NVIDIA cards
When using FreeSync with a compatible NVIDIA graphics card in G-SYNC compatibility mode, LFC behaves slightly differently than it does with AMD cards.
LFC triggers regardless of the monitor’s FreeSync range.
Therefore, if your monitor has a VRR range of 120-144 Hz and you get 60fps, the monitor refresh rate will change to 120 Hz, whereas with AMD cards, the LFC will not work and you will get a fixed frequency of 144 Hz (or 60 Hz if VSYNC is working).
In addition, the LFC threshold is usually different when using an NVIDIA GPU. For example, with many 48-144Hz FreeSync monitors, the LFC runs at about 60 fps with NVIDIA cards!
Because of this, FPS fluctuations around the LFC threshold will cause the monitor to go up and down rapidly with refresh rates, causing brightness flicker.
Here is what you can do:
If you have a 144Hz monitor with a VRR range of 48-144Hz, you can use CRU to reduce the range to 90-144Hz.
Since there is not much difference in brightness at 90 Hz and 144 Hz, the flicker will not be noticeable – or it will be much less noticeable. Therefore, between 90 and 144 frames per second, you will get smooth VRR performance.
In more demanding games, you need to limit the FPS to 72 or lower (to keep the FPS from exceeding 72).
Below 72 FPS, the LFC will double (45-72 FPS) or triple (30-48 FPS) the frame rate to a VRR range of 90-144 Hz to prevent image tearing – again without noticeable brightness spikes.
However, this means that between 72 and 90 FPS, you will not get a variable refresh rate, but depending on the game and your FPS, you can experiment with wider VRR ranges, such as 80-144 Hz.
If there is no FPS tracker or FPS limiter in the settings of the game you are playing, we recommend using RTSS.
The reduced refresh rate method
If the frame rate of a particular game is mostly around 60 FPS and you have a high refresh rate gaming display, consider lowering your monitor’s refresh rate to 60 Hz to avoid brightness flicker.
This can also help with other problems, mostly related to games locked at 60 FPS.
When you reduce your monitor’s refresh rate, make sure that you also choose the appropriate response time acceleration setting.