no signal from laptop via hdmi *help needed

ZigiKosta

Member
hello, I am new here this is my first post and i would really appreciate some help.
I have a Optoma UHD35 projector 2021 model and a hp spectre laptop on windows 10 (4k resolution, about 5 years old) and when i connect them via HDMI all i see is a no signal message on projector screen.
When i connect my laptop via hdmi to my tv or my other projectors (even 4k ones) it all works fine so i know the hdmi output works fine.
I tried many different hdmi cables (none longer than 5 meters) even the most expensive ones but nothing seems to help.
The projector only projects a no signal message.
i tried the basic hdmi handshake troubleshooting with booting the device while connected in different orders and turned off auto searching on the projector but no luck.
Now the thing that is really weird is that my laptop knows it is connected, while connected via hdmi the screen blinks and optopa UHD35 is listed as an audio output option. the other weird thing is that while trying out different things i resorted to unplugging and plugging the hdmi back and forth in my laptop output. one of the tries was succesful and i got the picture projected perfectly (on around the tenth attempt of replugging the hdmi) everything was working smooth until i changed the laptop resolution while it was being connected from UHD to full HD because i wanted to try the 3D feature. the second i clicked approve on the change resolution pop up message the picture got disconected and the dreaded no signal message appeared again. Since that i changed my laptop resolution back to 4k and tried unplugging and replugging about 1000 times but zero luck, i never got the conection to work again.

I know this is a lot to read but i hope someone will take the time to reply, I am really desperate as i paid over 1000 euros for the projector and the salesman said he couldnt help me with this issue since i had already gone through the basic troubleshooting and he doesnt know what else there is to try.

thanks in advance to anyone who will reply
 

ashyt16

Active Member
For now I would just try 1080p and 30hz as the starting point. 4k can be a pain to get right for projectors as there are other factors to consider like cable type and length.
Does it work with other sources?
What does it state in the signal info of the PJ menu?

Also make sure that your laptop is in the right mode for outputting to an external display.
You can either use the control panel.of your graphics drivers or press the Windows logo key + P.
 

Joe Fernand

Distinguished Member
AVForums Sponsor
HotPlug - I would be wary of your 1000 connect/disconnects, HDMI sockets can be easily damaged.

Laptop - want to see a Monitor with the relevant EDID and can be finicky when connecting to a ‘Home Cinema’ device such as an AVR or Projector.

You may want to consider a device which sits between the Laptop and the Projector and supplies the constant EDID the Laptop requires.

You can download Monitor Asset Manager from Entech.tw to get some idea of what the Laptop is seeing when connected to the Projector.

The HDFury Dr HDMI 4K is the EDID manager we would supply/install.

Joe

 

ashyt16

Active Member
Dont take this the wrong way and I've heard great things about the fury, but I don't think its necessary to go to the expense with the setup he has.
In fact I dont think any hardware EDID management would be required as Windows 10 supports software EDID management if the graphics drivers support it.
 

Joe Fernand

Distinguished Member
AVForums Sponsor
I’ll let folk know :)

As you say a short HDMI cable between the Laptop and the Projector and aim to force the Source into a low resolution mode and then, assuming you get a stable image, see how it goes as you increase the resolution.

Also worth checking the capabilities of individual Inputs on the Projector - they may not all support the same formats.

Our experience is no matter if it’s WIN10 or otherwise you often require the EDID manger to sit between the devices when a computer is involved.

Joe
 

ZigiKosta

Member
For now I would just try 1080p and 30hz as the starting point. 4k can be a pain to get right for projectors as there are other factors to consider like cable type and length.
Does it work with other sources?
What does it state in the signal info of the PJ menu?

Also make sure that your laptop is in the right mode for outputting to an external display.
You can either use the control panel.of your graphics drivers or press the Windows logo key + P.
-it doesnt work with either resolution now. it only worked once on 4k until i lowered the res as stated above.
-it says no signal found
-yes i tried all of the options but none worked (duplicate,...)
 

ZigiKosta

Member
For now I would just try 1080p and 30hz as the starting point. 4k can be a pain to get right for projectors as there are other factors to consider like cable type and length.
Does it work with other sources?
What does it state in the signal info of the PJ menu?

Also make sure that your laptop is in the right mode for outputting to an external display.
You can either use the control panel.of your graphics drivers or press the Windows logo key + P.
also yes it works with other sources with no problem, i tried many different hdmi cables but zero luck and both ports are 2.2.hdcp on the projector
thanks for the reply
 

ZigiKosta

Member
HotPlug - I would be wary of your 1000 connect/disconnects, HDMI sockets can be easily damaged.

Laptop - want to see a Monitor with the relevant EDID and can be finicky when connecting to a ‘Home Cinema’ device such as an AVR or Projector.

You may want to consider a device which sits between the Laptop and the Projector and supplies the constant EDID the Laptop requires.

You can download Monitor Asset Manager from Entech.tw to get some idea of what the Laptop is seeing when connected to the Projector.

The HDFury Dr HDMI 4K is the EDID manager we would supply/install.

Joe

thanks for the idea, will check on it.
 

ashyt16

Active Member
also yes it works with other sources with no problem, i tried many different hdmi cables but zero luck and both ports are 2.2.hdcp on the projector
thanks for the reply
So the laptop is the issue. Regarding the display output what graphics chip does your laptop use?
 

DB9S

Active Member
also yes it works with other sources with no problem, i tried many different hdmi cables but zero luck and both ports are 2.2.hdcp on the projector
thanks for the reply
Is the laptop HDCP 2.2 compliant? 5 years old, possibly not.
Also check the projectors max computer resolution. Often different to video resolution.
 

ZigiKosta

Member
Is the laptop HDCP 2.2 compliant? 5 years old, possibly not.
Also check the projectors max computer resolution. Often different to video resolution.
but if it is not compliant how is it possible that i managed to get a connection on one occasion?
would installing this software help me determine the issue?
it says it Reads and generates reports based on Extron display data

to answer your second question, the one time i managed to get a connection the resolution was UHD so i dont think it is lower than the video resolution
 

DB9S

Active Member
but if it is not compliant how is it possible that i managed to get a connection on one occasion?
would installing this software help me determine the issue?
it says it Reads and generates reports based on Extron display data

to answer your second question, the one time i managed to get a connection the resolution was UHD so i dont think it is lower than the video resolution
Try lowering the refresh rate to 30hz or lower and see if it works.
Another thing to try if you want to keep a high refresh, is to lower the bit depth of the laptops signal to 8 bit.

l
Computers/laptops will want to send RGB signals as a preference, and if 10 bit or more @ 4k res, it is not a 'legal' HDMI signal.
4:4:4/RGB needs to be at 8 bit or less for 50 or 60hz (or higher).

Dropping to 8bit or 30hz will lower bandwidth enough to take decent cables out of the equation.
Also, Have you tried another laptop?
Good luck.
 

ZigiKosta

Member
Try lowering the refresh rate to 30hz or lower and see if it works.
Another thing to try if you want to keep a high refresh, is to lower the bit depth of the laptops signal to 8 bit.

l
Computers/laptops will want to send RGB signals as a preference, and if 10 bit or more @ 4k res, it is not a 'legal' HDMI signal.
4:4:4/RGB needs to be at 8 bit or less for 50 or 60hz (or higher).

Dropping to 8bit or 30hz will lower bandwidth enough to take decent cables out of the equation.
Also, Have you tried another laptop?
Good luck

YES YES YES!!! I LOVE YOU!!!
it was set to UHD 60 hz, i switched to 30 and it is working now!
strange since the projector input says 60hz 4k and it is also capable of 240hz at 1080p

I am so grateful to everyone who helped me on this thread
 

DB9S

Active Member
YES YES YES!!! I LOVE YOU!!!
it was set to UHD 60 hz, i switched to 30 and it is working now!
strange since the projector input says 60hz 4k and it is also capable of 240hz at 1080p

I am so grateful to everyone who helped me on this thread
Great stuff. You are welcome.
It isn't just as about the rated max refresh and resolution, it is to do with 'legal' HDMI signals.
Glad you got it working.
 

ashyt16

Active Member
YES YES YES!!! I LOVE YOU!!!
it was set to UHD 60 hz, i switched to 30 and it is working now!
strange since the projector input says 60hz 4k and it is also capable of 240hz at 1080p

I am so grateful to everyone who helped me on this thread
This was mentioned in post 2!
 

DB9S

Active Member
This was mentioned in post 2!
Sort of. ;)
1080p 30hz would work regardless and even with iffy cables. It was 4k that was required and the issue was it was being sent at what would appear to be 60hz RGB 10bit. Not a legal HDMI signal. Display port would be fine however.
Everyone was thanked for their assistance too.... :)
 

ashyt16

Active Member
Sort of. ;)
1080p 30hz would work regardless and even with iffy cables. It was 4k that was required and the issue was it was being sent at what would appear to be 60hz RGB 10bit. Not a legal HDMI signal. Display port would be fine however.
Everyone was thanked for their assistance too.... :)
Granted, but if the OP had said yes fine at 1080p and 30hz next suggestion would have been 4k at 30hz, problem solved.
But glad it's sorted.
 

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