Mixing the worlds of PCs and TVs can be a tricky task. PCs are made for the most part to be used with monitors and when using a PC with a TV, you may encounter some issues, with screen flicker being one of the most common.

Why does screen flicker happen and what can we do to fix it? Let's take a look at some of the most common reasons.

Not all HDMI cables are created equal and making sure you buy a good quality HDMI cable is important. Good quality HDMI cables can come with better shielding for damage resistance, higher quality materials to prevent stiffening or bending over time, more robust connectors that do not break as easily or even EMI shielding for use in environments with a lot of electromagnetic interference. Poor quality HDMI cables can also struggle if they are long in length. A poor quality 3-5 meter cable will be much more likely to have issues than a higher quality one.

You don't need to spend an exorbitant amount on cables, but buying cables from untrustworthy manufacturers can result in issues. We recommend HDMI cables from Ugreen and Vention as we have found their products to be reliable.

There are also many versions of HDMI, from version 1.0 released in 2002 all the way up to 2.1 released in 2017, and each device and cable will have support for different versions. That's a complicated topic in itself, and for the most part, you don't have to worry about it as each new version of HDMI is backward compatible, meaning that you can still use older version HDMI cables with newer version HDMI equipment. Note though that higher version HDMI cables will support more features and higher transmission bandwidth. For example, an HDMI 2.1 cable can support a 48Gbps transmission rate compared to 10.2Gbps on HDMI 1.4 cables and also support higher refresh rates at different resolutions and additional color spaces and color depths. We recommend using an HDMI cable that matches your TV. If you have an HDMI 2.0 TV, then try to get an HDMI 2.0 cable.

The refresh rate is one of the most common reasons for screen flicker and you should definitely check this before going out and buying new cables. At a basic level, you should make sure that you are not using a refresh rate that is not supported by your TV.

If you are connecting your PC to your TV via HDMI, what refresh rate you can use will depend on what version of HDMI your TV supports. First find what version of HDMI your TV supports, and then look at the following to see what refresh rate you should be using.

HDMI 1.4 does not support 4K content at higher refresh rates than 30hz, it's basically just made for 1080p HD content.
- 1080p content at up to 144hz
- 2k content at up to 75hz
- 4k content at up to 30hz

HDMI 2.0 can handle 4k at 60hz and 1080p at even higher refresh rates and is currently the standard consumers should shoot to get.
- 1080p content at up to 240hz
- 2k content at up to 144hz
- 4k content at up to 60hz

HDMI 2.1 is a new standard which supports up to 8k and 4k content at higher refresh rates, but for the most people this will just be overkill and it is really a standard that will only be widely used in the future.
- 1080p content at up to 240hz
- 2k content at up to 240hz
- 4k content at up to 144hz
- 8k content at up to 30hz

As a general rule of thumb, try to set the refresh rate on your computer to 60hz, as this will be the best fit for most TVs. If this doesn't work for the content you are sharing, you may need to bring your refresh rate down to 30hz. This isn't optimal though as 30hz will be noticeably different, and you should try to bring down your resolution instead.

To change the refresh rate on your PC, follow these guides:

Changing other display settings can help as well. Make sure that you are using display settings optimized for your TV and not your built-in screen. In one instance, we found that changing the resolution from 1080p to 1080i helped get rid of screen flickering, as that was the display setting the TV was using.

If you have a PC with a discrete video card, there may be settings set by the video card that you need to change. The best way to go about this is to get support for your specific video card for TV screen flicker. You can also research online and find others who experienced TV flicker when using the same video card and were able to find a solution.

Sometimes there may be settings on the TV that you need to change to get rid of screen flicker. The best way to go about this is to get support for your specific TV. You can research online and find others who experienced TV flicker when using the same TV and were able to find a solution.

Finally, test the TV with another source other than your PC as the screen flicker may be a sign of a broken TV. If a screen flicker is occurring because the TV is broken, you want to contact your manufacturer's support team and try to get the warranty if available.

While monitors are a little bit out of the scope of this article, many of the concepts here apply to monitors as well. You'll often use different connectors like VGA, DVI, or Display Port for monitors and you would have to research those connectors to see what they support.
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