How to Split an HDMI Signal to Multiple Displays


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Jul 06, 2023

How to Split an HDMI Signal to Multiple Displays

HDMI splitters can help you solve HDCP errors. Learn how to split an HDMI signal

HDMI splitters can help you solve HDCP errors. Learn how to split an HDMI signal and which HDMI splitters are worth getting.

HDMI splitters (and graphics cards) can send a single video signal to two HDMI monitors at the same time. But not just any splitter will do; you need one that works well for the least amount of money.

We'll first discuss why finding the right splitter is so hard and then recommend the three best HDMI splitters, plus an HDMI-splitter alternative, and HDMI cable.

An HDMI splitter takes an HDMI video output from a device, like a Roku, and splits it into two separate audio and video streams. Once split, you can then send video to two separate monitors from a single source.

Unfortunately, most splitters suck. Many don't work because of an anti-piracy measure built into hardware called High-Bandwidth Digital Content Protection (HDCP).

HDCP is an anti-piracy measure built into streaming devices, televisions, cables, and even browsers, like Chrome and Safari. All of these components and programs use HDCP to prevent illegal duplication by using a verification process between the video-playing device and the screen.

After establishing a verified connection, HDCP encrypts the signal to prevent unauthorized recording of the content. HDCP's encryption makes split video unwatchable. Unfortunately, this arrangement also prevents content owners from viewing their own content sometimes.

If the video is HDCP-protected, but one part of your setup isn't HDCP-compliant, the video won't play (sometimes with an error message). That means a lot of people with older equipment can't watch legally-purchased content or make archival copies of such materials.

HDCP 2.3 is the latest version of the HDCP copyright-protection scheme. It's reverse-compatible with older versions of the format, although if you're trying to watch 4K content that has been protected with 2.3, there are additional hurdles to jump over. For example:

HDCP 2.3 is best summarized as the same standard as 2.2, except that it's been modernized to patch previous vulnerabilities while also protecting 4K, or Ultra-High Definition (UHD) content from piracy.

Fortunately, even the latest version of the HDCP standard still supports Fallback Mode.

There is a "Fallback" mode inside HDCP that allows for HDCP-compliant content to "fall back" to a lower resolution (usually 720p or 1080p) if you're using a non-compliant device. However, Fallback mode rarely gets triggered by devices other than a splitter, which is why they're a great solution to this issue.

Some cheap splitters bypass HDCP entirely by accident. Because cheap splitter manufacturers didn't bother paying for an HDCP license, they shouldn't be able to play protected content at all. However, because they trigger Fallback mode, the content gets downgraded to a lower resolution and plays normally. Most of the time, at least.

If you'd like to find a splitter on your own, some features to look out for are:

But if you just want a splitter that's reported to work for mirroring your video, with a high probability of working, keep reading.

There are two common kinds of HDMI splitters: 1x2 and 1x4. A 1x2 splitter has two outputs and one input. A 1x4 splitter comes with one input and four outputs. I could not locate any 1x4 splitters that trigger Fallback mode. But there are plenty of 1x2 splitters that do so.

Both these splitters have identical features, which suggests they're made by the same manufacturer. Each supports and strips HDCP and includes a power adapter. On Amazon, they also both get great reviews. The Orei gets an average score of 4.4 stars out of five.

The ViewHD gets an average score of 4.3 stars out of five. Does that mean the Orei is a better device? Judging from the reviews, they're almost identical.

Most 1x2 HDMI splitters are made by the same company and rebranded. For example, at Walmart, a cheaper HDMI splitter sells for less than $14 and appears identical to the Orei and ViewHD devices. Judging from the reviews on Walmart, it provides the same function as the other two splitters.

If you own a desktop (or a laptop with an external graphics card), you can split an HDMI signal using a graphics card with dual video outputs. It works just like a splitter, except it doesn't reliably remove HDCP. But provided all the components in your media setup are HDCP-compliant, you only need to plug in a GPU and set up your operating system to mirror the screens. This process is ideal for people who own desktops and has the advantage of also splitting the audio signal between two HDMI displays.

With prices for gaming graphics cards now almost back to normal levels, you might just want to order a relatively inexpensive NVIDIA 1050 Ti with dual-HDMI outputs, or another of our picks for best gaming graphics card,

While GPU prices are falling, if you're not a gamer, we recommend the least expensive graphics card with multiple video outputs: that's the low-profile MSI GT 710. It's terrible for gaming, but it's sufficient to get two monitors working (potentially with an adapter). Unfortunately, video output through the VGA port isn't supported by HDCP, although if it does trigger Fallback mode, the video will downscale to 1080p. In other words, HDCP content only sometimes plays over the MSI GT 710's VGA port.

On the downside, the MSI GT-710 won't handle 4K Netflix streaming or even 4K video output. And when we say it's terrible for gaming, it's practically unusable for anything but low resolution, older games. You're better served by most modern integrated graphics than a GT 710.

The most important specification to note is that the graphics card uses HDCP version 1.3, so it may trigger HDCP Fallback mode, but I can't guarantee that it does. But if it doesn't trigger Fallback mode, it won't work with the latest version of HDCP, which means all your HDCP 2.3 content may not play.

For those who already own a GPU, you can split your video output into two HDMI-equipped monitors using a converter. The most common video display port is DVI. That's why a DVI-to-HDMI adapter can turn any DVI port into an HDMI video output. Unfortunately, you can't pass audio through a DVI port. So it's best used if you have some other way of getting sound working, like an auxiliary audio cable.

A common error that you might see on set-top boxes and gaming machines is the HDCP Unauthorized Content Disabled message, particularly on the Roku.

If you get the error, consider yourself lucky. Most people only get a blank screen and rage. In this situation, one component of your setup lacks HDCP support. Normally, that's either the splitter or the cable.

If you know your display and video source are HDCP-compliant, consider just getting an HDCP-compliant HDMI cable.

If you're stripping HDCP, you won't need any compatible equipment. However, in case you want to one day play high-definition HDCP-protected content, you might want an HDCP-certified HDMI cable.

This was the cheapest cable we could find that includes compatibility with the latest version of HDCP as well as HDMI 2.0 support, which means up to 8K resolutions at 60Hz refresh speeds.

If you plan on copying and distributing the content, yes, it's usually illegal. However, for the purposes of recording yourself playing video games, making legal backups of property you own, and other fair-use applications, it's not illegal. However, there is some legal gray area here as breaking or circumventing copyright protection potentially breaks the law. The US Copyright Office offers a page on Fair Use Laws. For those with the time, please visit the page to verify that your particular needs fall within the law.

Splitting your HDMI video signal onto two monitors is easy. It requires using an HDCP-compliant component chain or a cheap HDCP splitter. Unfortunately, because of flaws in the HDCP copyright protection scheme, and continuous upgrades to the technology, there is no reliable way to get video working 100% of the time.

Kannon Yamada holds degrees in Journalism (BA) and International Affairs (MA). He has written about Android, Home Office, Wellness, and Hardware Reviews since 2010. He started at MakeUseOf Answers in 2010, editing it from 2013 until 2015. Since then, he developed and edited the Buyer's Guide section (2016-2018), and currently is MakeUseOf's SEO Researcher.