The Quickest Way to Solve Your EDID Issues

What is EDID? Why is it Important?

A Business Card to Clarify Specifications

EDID is like a business card that includes a serial of information. It describes the specification of a display device, such as manufacturer, product ID, serial No., production date, monitor size, supported resolutions, and frame rate...etc.

There are so many display manufacturers in the A/V market and each has different specifications. Without EDID, video sources can hardly communicate with display devices, thus causing resolution unmatched between video sources and displays. The most common issues are black screen, image distortion, flickers...etc.

How Does EDID Work?

Create Common Ground for Sources and Displays

EDID allows video sources and display devices to communicate in the same "language". Given that, a monitor can tell a video source what resolution it can support and the video source can properly provide the corresponding signal. This communication process is initiated as soon as the monitor and video source are connected via a cable and powered on. However, EDID can be much more complicated when you have multiple video sources and monitors. We will cover more details for you at the end of the article.

Most Common EDID Issues

We have been in the industry for more than 20 years and handle a variety of EDID issues for customers around the globe. In the following, we're going to share the most common issues and their solutions for you.

Issue: No Video Shown

Possible Cause: EDID is broken or incorrect

The EDID is broken or incorrect so that your A/V source is unable to recognize the EDID information of your screen.

Solution

Apply an EDID emulator for your monitor to properly send EDID to your video source.

Issue: No Video Shown after Switching to a New Source

Possible Cause: Different HPD signal

This often happens in A/V integrations, because different A/V equipment manufacturers use different HPD (Hot Plug Detect) signal to communicate. 

Solution

Use an HDMI repeater or distributor to separate HDP signal, allowing the video output and input communicate with HDP respectively.

Issue: Resolution Mismatch between a Source and a Display

Possible Cause: EDID Unrecognized

When your PC is unable to recognize EDID, it will automatically switch to a default resolution. At the moment, If you manually switch to a resolution of your display to match that of your video source, some graphics card drivers will enforce to a lower resolution. This inconsistency will thus cause resolution mismatch.

Solution

Try to manually switch to a mutual resolution that both devices can support. If EDID of your display is broken, you can use an EDID emulator for your monitor to allow the video source to read EDID.

Possible Cause: Graphic Card limitation

Even though your A/V source is able to read the EDID of your display, the communication process can still go wrong. Some graphic card drivers limit the output resolution at 1024 x 768, a resolution most display devices can support. However, If the native resolution of your display does not match 1024 x 768, the font size might appear with errors.

Solution

Manually switch to 1024 x 768 for your monitor or use an EDID emulator for your display to set up a common resolution supported by your source.

Possible Cause: Difference between Displays

EDID can also go wrong when your video source is connected to multiple displays with different native resolutions. Since one video source can only read EDID from one display at a time, the resolution mismatch will happen in the displays with unread EDIDs.

Solution

Switch to a resolution supported by all monitors. You can also use an HDMI distributor that has EDID management to set up resolutions for each output.

Although we do not produce EDID emulators, your can still solve EDID issues with our products that have built-in EDID emulators, such as HDMI distributors, switchers, and matrix switchers...etc. For the next chapter, we're going to explain the technique of how EDID is processed for multiple monitors and sources.

How to Handle EDID with Multiple Monitors and Sources?

EDID in Distributed A/V Systems

A professional A/V system usually includes more than one A/V source and one monitor, and it's very likely using HDMI distributors, switchers, and matrix switchers for A/V setups. That also means EDID communication will become more complicated. As a professional A/V manufacturer, we're going through how EDID is handled in distributed systems.

Managed EDID without Scaler

Manufacturer like SC&T has HDMI distributors, switchers, and matrices that support EDID management. They save EDID information and send it to your HDMI source and then the video source will send back the corresponding signal that supports the lowest common resolution between your HDMI monitors (Make sure you connect the monitor with the lowest resolution to the first output port). If you're not satisfied with the low resolution, you can manually switch to higher resolutions for each monitor.

Managed EDID with Scaler

Moreover, we provide devices with advanced features which have not only support EDID management but also a scaler function. The scaler allows video sources to send the highest resolutions that each of your monitors can support.

Models with EDID Management

SC&T HDMI Splitters

Including 1 in 4 out and 1 in 10 out models that support HDMI 2.0, HDCP 1.4, LPCM 7.1, Dolby TrueHD, and DTS-HD Master Audio for your professional A/V setup.

HD04-4K6G - 4K 60Hz 1 x 4 HDMI Distributor Amplifier

HD10-4K6G - 4K 60Hz 1 x 10 HDMI Distribution Amplifier

SC&T HDMI Matrix Switchers

Including 4 in 4 out and 10 in 10 out models that support HDMI 2.0, HDCP 2.2, HDR 10, LPCM 7.1@192KHz, Dolby TrueHD, DTS-HD MA audio and have audio extractor function to create more possibilities for your audio environment.

HS04M-4K6G - 4K 60Hz 4 x 4 HDMI Matrix Switcher Built in Audio Extractor

HS10M-4K6G - 4K 60Hz 10 x 10 HDMI Matrix Switcher Built in Audio Extractor

Models with EDID Management and Scaler

SC&T HDMI Distributors

Built-in a video scaler that can up/ down-scale an native resolution to desired one and having multiple audio interfaces to help you build up your professional A/V system.

HAE01 - 4K 60Hz HDMI Audio Extractor with Up/down Scaler

SC&T HDMI Matrix Switchers

4 in 2 out design for home theatre, and built-in audio extractor and video scaler to better manage your A/V setup.

HS42M-4K6G - 4K 60Hz 4 x 2 HDMI Matrix Switcher with Audio Extractor & Scaler

Author

FAE
Ben Wang

We have worked with companies around the world for more than 20 years. From experience, we construct an efficient method to analyze your situation and provide immediate help.