Second monitor: red dots all over the screen

[Victor99]

Hi,

I've got an issue when connecting my notebook to a TV (Samsung) or monitor (Philips) through an HDMI connection.

The image is displayed but there's a bunch of red dots scattered all over the screen.

I've tried with a different laptop, same cable and display, and it works fine, therefore, the issue is on my notebook.

I also tried changing the video resolution but I got the same result (notebook's top is 1366x768).

Can anyone help me?

Thanks.

[praveenbv]

Hi@Vuty, Welcome to the HP Support Community!

I understand that you have an issue with the second monitor bunch of red dots. 

May I know its  HP Monitor?

Please find the picture looks the same, let me know.

Hope this helps! Keep me posted. 

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

Click the “Kudos, Thumbs Up" on the bottom right to say “Thanks” for helping!

Have a great day! 

[Victor99]

Hello Praveenbv,

thanks for your answer, but I really don't understant what you mean.

I don't know how to enclose an image here, maybe I can't.

Here you have two photos of the problem, with different screen resolutions and different red pixel patterns:

https://we.tl/t-N6QAUKCH45

With some images I get cyan horizontal lines.

Monitor says 1920x1080 resolution for best results, the same as my TV, I think, but laptop's maximum is 1366x768.

Monitor, TV and HDMI cable work fine with other devices, so the issue is with my HP laptop.

Thanks

[praveenbv]

HI@Victor99,

To isolate the issue we will perform few steps, firstly to update the display drivers 

You may also check if the same red dots show up on the BIOS screen 

Try this steps as well .

Search for and open Display settings. You can also right-click the desktop and open Display settings. Scroll down and click Advanced display settings. In the Display adapter properties, click Display adapter properties.

Click on the Monitor tab to adjust the Screen Refresh Rate from the drop-down menu. 

If the issue still persists, try re-installing the driver - 

1) In the search box on the taskbar, type Device Manager, and then select Device Manager from the list of results.

2) In Device Manager, expand Display Adapter. 

3) Right-click on the Display Adapter, and then select Uninstall device > Delete the driver software for this device check box > Uninstall.

4) Restart the computer. 

Also, try updating the computer using these steps -

Step 1 Windows Updates - 

1) In the search box, type and open Windows Updates. 

2) Check for updates. 

3) If the updates are available, click on install and restart the computer. 

Step 2 HP Support Assistant Updates - 

1) In the search box, type and open HP Support Assistant. 

2) Check for updates. 

3) If the updates are available, click on install and restart the computer.  

I understand you want to know if there is a screen calibration that can make your screen look better than the other monitor's you have,

I'll be glad to help you out, however, for an accurate solution I will need more details:

What is the product number of your product? Use this link to find it: http://support.hp.com/us-en/document/c03754824 

When was the last time it worked without these issues? Have you attempted a system restore?

About the other 3 computers, are they similar models or different ones?

In the meantime, please try the steps mentioned on this link: Click here

Please reply with the details for further assistance.

Please share the pictures of BIOS.

[Victor99]

Hello.

When into BIOS, no image is displayed on the secondary screen. I don't know how to tell the laptop to use the secondary monitor as I need to be into the OS to select the output device. If there's a way to do it, please tell me.

I reinstalled the driver as you told me to do. Plus, I went though Windows Update and HP Assistance. I tried to install a different graphics driver (in the HP Assistance list) but the hardware did not support it.

I tried once more the display settings, resolution, frequency and so no. I finally found a combination that, at least, makes the monitor switch on in Windows (the images I attached were with Ubuntu). It is 1920x1080 and 60i. The rest of them don't work.

It's curious that Windows 10 only offers this resolution on the primary screen if the secondary is connected. Otherwise, primary screen top resolution is 1366.

With these parameters (1920x1080 and 60i), my secondary monitor (Philips) switches on and displays the image, but it goes black for two seconds every now and then. It's really annoying.

Colors are still bad, I couldn't make it work. I tried the website you suggest but I got nothing.

Answering your question, it never worked on a secondary screen. I always had the colors issue. The fact is I didn't mind because I never had to use a secondary screen... until now 😞

The other laptop I've used with this monitor is an HP Probook. The monitor works fine with this computer.

Here you have my number of product: K4C70EA#ABE

I think that's it so far.

Thanks for your help.

[praveenbv]

H@Victor99,

We have done the basic troubleshooting as per the document and the notebook needs to checked taking remote access so that get to know it's a hardware or software issue.

I'd suggest you contact HP in your region regarding the service options for your computer or HP Chat Support Team.

If you are having trouble navigating through the above options, it's most likely because the device is out of warranty. If yes? please send me a private message with the region you are contacting us from. Check next to your profile Name, you should see a little blue envelope, please click on it.   

Have a great day!  

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution. 

Click the “Kudos, Thumbs Up" on the bottom right to say “Thanks” for helping! 

[Victor99]

Yes, my laptop is out of warranty, so I prefer to go on with you, if possible, specially now that you already know the issue.

However, I cannot see any blue envelope next to my profile name, sorry.

My region is Palma (postal code 07004, Balearic Islands), Spain.

Thanks for your help.