No Signal Issue:
The Ad board is auto detection in design, if no video signal detected OSD MENU item cannot be shown on screen, however you can press AUTO button to search next input. We have another composite AD board can show pup-up menu for input source selection, but it’s not auto detection and without DP port.
If you test the monitor with 6ft cable connect directly to PC(without other extension or extender) is still couldn't resovle the issue, problem should comes from other reason. The monitor can EPM/ECH/EPM auto detect input signal sources (VGA, DP or HDMI), and plug&play monitor depends on EDID, DDC to communicate with PC. The best resolution of this for example 8.4” monitor is 800x600@60Hz, EDID data can be read by tool or utility, for example, MonInfo (Monitor Asset manager) utility of EnTech.
Also please check all the steps, especiallly the step 5. You need to set the display to the right solution at 60Hz
E-EDID
Here is another acronym for you. E-EDID stands for Enhanced EDID. This allows the devices to handle additional data, including vendor-specific specifications, as it opens up the data strings to 32 Kilobytes.
It's just another way for your electronics to get a conversation going, but with a little more information.
EDID Troubleshooting
The first step when you're having issues you believe are related to EDID is to determine if it is the source device causing the issue.
Step 1
Connect the device directly to the DISPLAY with nothing in between to see if this solves the problem. If it does, then it's the middle man causing issues.
Step 2
If it still fails to work, try connecting the source to a different DISPLAY that you know to be reliable. If this also fails, then your problem most likely lies with the source.
Step 3
Try updating the manufacturer firmware for whichever device you believe to be the troublemaker. This often takes care of the problems quickly and easily.
Step 4
Check the length of the cables you are using. The HDMI signal depends largely on the power of the device to which it is connected. Typically, HDMI can be transmitted up to 50 feet without issue, but some devices just don't output enough power to make it past 30 feet or less (computers and gaming systems).
If the device isn't producing enough power, the signal isn't going to make it to its destination and the source will never get its EDID from the display. Splitters, switches, and of course, extenders, give that signal a boost to carry it further, but these also come with limitations. Check the device's manual to ensure your cables are not too long for the run.
Step 5
Is your source a computer? Many DISPLAYs only accept specific computer resolutions. Make sure the resolution you are attempting to achieve is supported by your DISPLAY.
There are a number of different reasons your HDMI compliant devices might have trouble communicating, but hopefully this will get this you started if you're experiencing issues! Remember, it may not always be the case that you're working with defective devices. It could just be a missed communication