Dual/Triple Monitor KVM Switch Black Screen Troubleshooting Resolution of the monitor

Computer output capabilities are limited

It is recommended that you refer to your computer's official website to check the specifications. For example, some older PCs may not support outputting two 4K 60Hz video signals simultaneously, but they should be able to handle two 1080p signals without issue. In this case, lowering the resolution usually solves the problem.

The EDID reading is abnormal

It means that the video signal being output exceeds the recommended resolution and refresh rate. This usually happens when the monitor's optimal resolution refresh rate is higher than the KVM's optimal resolution refresh rate. "To confirm this problem, you can judge by comparing the output parameters of the expansion screen when connecting directly and through KVM; or through professional EDID reading software to confirm(you can consult customer service to get it). In some cases, the problem can be solved by hot-plugging the input cable on the PC side or restarting KVM".（For best results, start by powering on the monitor, followed by the KVM, and then connect it to the PC.）

Video bandwidth exceeds the maximum limit

It will happen when the input source device and the monitor support the G/F-Sync function at the same time. Please try to turn off the HDR10, G-Sync, and FreeSync of the device.

Cable issues, like length or quality

The cable exceeds the specified length, or the quality is not good, which may cause a flickering screen. Please try to change to better quality cable. Check if the length of the HDMI/DP cable meets the specifications below because the corresponding cable length will directly affect the output resolution. Our KVM is equipped with a 1.5m 4k@60hz HDMI input cable.

•  When using 4K@60Hz as the input source, the output HDMI cable should be less than 5 meters.
•  When using 4K@30Hz as the input source, the HDMI cable at the output end should be less than 10 meters.
• When using 1080@60Hz as the input source, the output HDMI cable should be less than 15 meters.
• For the DP cable, it is recommended not to exceed 1.8 meters.

If all of the steps above cannot help you locate and resolve the problem, please contact TESmart Customer Support for further assistance. Briefly mention the steps that you’ve already tried for a faster solution.