What is flickering and how to prevent it from appearing

Have you ever heard of flicker-free monitors ? If you are a gamer or are looking for a new monitor, terms such as flickering, ghosting or bleeding will surely appear quite frequently in their specifications, so it is convenient for us to know what this phenomenon consists of and especially how to avoid it as much as possible..

In addition, we will give you some generic advice on how to deal with the problem and the consequences that it may have in the long run on us or our image experience.

Index of contents

What is flickering on a monitor

Flickering, or flicker in Spanish, is the change in light intensity of a monitor in very short intervals. In other words, it is the frequency or number of changes per second at which the change between the brightest and darkest light occurs.

As we know, today's LCD-TFT monitors generate the image thanks to a panel of pixels that more or less obstruct the light behind us. The electricity that circulates through both elements is always refreshed a certain number of times every second, causing transistors to lose the intensity of light they generate or are letting pass for a short period of time. These intervals are basically flickering, and as you can imagine, it is related to the refresh rate of the monitor.

Flickering due to refresh rate

Depending on the refresh rate of a monitor, our view may or may not catch flickering in the image pane. This is highly dependent on the frequency at which the monitor image signal is regenerated. The refresh rate of a monitor is the rate at which a screen updates its image per second, and is measured in Hz.

In the specifications of a monitor we can sometimes find vertical frequency and horizontal frequency. The one that interests us is the vertical, since the other is calculated by making the product of the vertical frequency and the number of horizontal lines on the screen. They are then all the existing lines on the screen that must be filled in a second. For example, a monitor with 2560x1440p resolution and 165 Hz (vertical frequency), is going to have a horizontal frequency of 1440 * 165 = 237.6 kHz in theory.

In current monitors, this phenomenon is difficult to perceive due to the high refresh rates of LCD, OLED panels and other technologies and variants, which are almost always above 60 Hz (100 times per second) and have technologies that precisely prevent the appearance of this effect when its frequency is low. Basically, it all comes down to delaying the loss of light of each pixel for each refresh as much as possible, and this is done by introducing transistors that let less energy escape in this tiny interval.

Surely if we have been in front of a traditional CRT (ass and glass) monitor, we will have perfectly noticed this flickering phenomenon, since the refresh rate of its electron gun was equal to the frequency of alternating current, that is, 50 Hz at most. At these frequencies, our eyesight is able to notice the flickering of the image quite clearly. The early LCD-TFT models also had this problem in a way, although the technology used was very different and the effects have clearly been reduced to almost zero today.

Flickering due to software

It is not always the fault of the monitor, especially if what we have is a current technology with a high refresh rate. Flickering can also be due to a bad software implementation, as you will all be thinking, in a poorly made game with performance bugs and graphic defects.

CPU and graphics card are the main hardware that is responsible for moving a game, and the graphics engine has not always been used in the cleanest way possible. This causes the textures, physics and effects transactions to not be carried out as it should, thus causing a little fluid processing and triggering errors such as flickering, or rather the well-known Lag. That moment when the game loses its fluidity and we clearly see the frames pass through our eyes slowly and with a huge blink.

This may be due either to a failure of the point graphics engine or at certain times of high detail load or to the limitations of our team, due to not being able to process everything the game demands. In any case, having a monitor with AMD FreeSync or Nvidia G-Sync will be a great advantage in this regard, since it is the monitor itself and GPUs that intelligently adapt the refresh rate to the needs of the game, increasing fluidity. and reducing aspects such as flickering and ghosting, which we will see in another article.

How to know if our monitor has flickering

We have already commented that every monitor is implemented with a certain refresh rate, the difference will be in whether or not our sight is capable of detecting its flickering. We already anticipated that in refreshment frequency above 60 we should not notice anything. Although internally, our eyesight is suffering from the effects of that flickering if it is really pronounced and the pixel technology is not adequate.

Common symptoms of flickering can be:

• Tired eyesight Temporarily blurred vision Headache Red, watery eyes

Of course this can appear even without flickering and being in front of a monitor for many hours.

The most effective and fastest way to know if a monitor has flickering is to take our smarphone or any other camera and start recording it. In this way we can capture what is happening on our monitor. If a monitor is flicker free, that is, flicker free, then in the video we will have a flat image as we see it.

Both in video and photo, on an LCD without Flickr lines will appear very close to each other, this is perfectly normal. We can take advantage of the slow motion mode of our terminal to record a video and see how these lines evolve over time. If we are lucky to have a CRT to compare, we will be able to see much less lines and very marked passing through the screen.

10 tips not to flickering on our PC

Well, we already know what flickering is and how it manifests itself on our monitor, and it is also clear that sometimes it is not the fault of the panel itself, but of the game itself or the lack of performance.

Here are 5 tips to avoid flickering directly on the monitor

• Check the specifications of your monitor: obviously if it is not flicker free, most likely this phenomenon will be noticed. If it is a somewhat old monitor, we can do little to fix this but buy a new one. Check the connection and the quality of the cable: sometimes the flickering is due to a bad connection between the monitor and the graphics card. Check that the cables are tight and free of slack. Especially on high resolution and high frequency monitors, a good cable makes all the difference, so please refrain from buying an HDMI / DisplayPort in the Chinese under your house. Check if the interface supports maximum performance: again we must focus on the connection. Normally in the specifications and instructions the version of the monitor and GPU ports comes in detail. We must ensure that both the GPU and the interface support the maximum performance of the monitor. For example, if we have a 4K monitor at 144 Hz and 10 bits, we will only get the maximum benefits with DisplayPort 1.4, while HDMI 2.0b is only capable of giving us 4K @ 60 Hz. Check monitor configuration: now we are going to address to the OSD panel, to check the monitor options. In it we will verify that, if we have dynamic refresh technology, it is activated (FreeSync or G-Sync). In some cases we have an overclocking mode or selection of different frequencies, so let's verify that it is above 50 Hz. Finally, the response time also influences the blinking, although more so in ghosting, again check that we have an high response. Check the GPU configuration: after the above we know that the monitor is fine, but what about the graphics card? In it, the dynamic refresh technologies must be activated if we have them, and the frequency and resolution must be the native ones that the monitor has. Many times a rescaling causes a lot of flickering, for example, placing 1080p resolution on a 4K monitor.

And 5 other tips to avoid flickering at the hardware and software level

• Check our hardware: obviously it is not the same to run Gears 5 on a Core i3 as it is on an i7, nor to do it in 1080p or 4K. We must be aware of the hardware we have and adapt the needs of the game to it. We can lower graphics, resolution, or do performance tests to see if the FPS is above 60, something basic to not have flickering. Having Windows in good condition: the window operating system often suffers from performance drops if we have never restored or formatted it, especially if we have updated the system several times. The first thing will be to optimize it as much as possible and remove everything that is left over, especially if the hardware is not very powerful. Having the DirectX, Open GL and Vulkan libraries updated will be essential for games to perform. Always have the graphics card driver updated: as important as the system is the graphics card driver. Manufacturers release continuous updates that fix internal bugs and optimize performance for the latest games. Perhaps this point is the one that gives us better results to improve performance. Having the game updated: the third main element is to always install the updates that are released from the game or software. These patches are always related to a performance improvement, so we update whenever we can to fix those bugs. Do not go so much and rest: it is not advisable to spend too many hours in front of a screen, but the view will tire and in the end we will be what causes this blinking in our sight. Resting is basic, and having a not too strong brightness on the screen helps, as does always activating the blue light filter.

Conclusions on flickering

We hope that with the previous tips and everything we have told about flickering, its origin and the influence it has on the gaming experience and our view have become clearer.

All this can be further improved with a good monitor, which does not always mean expensive, and a good calibration of our image panel. Let us always take advantage of the technology that the manufacturer makes available to us, especially dynamic refreshment, which will be widely used for this matter. Likewise, it is normal that a monitor with several years of use begins to suffer some other problem of this nature or its image, all of them have a limited useful life and are degraded.

We finish with some articles that we consider useful:

Does your monitor have flickering? Have you been able to identify the cause? Tell us your gaming experience with the monitor you have, it will always help other users in their purchase.