The screen is half dimmed on HP 27xq

[irritated28]

Good time. When turning on the computer, 1/4 of the monitor dimmed. After a few hours of work on 3/4. At the same time, when turning on it flickers around the entire perimeter.

[irritated28]

I have experience working with SMD electronics. If you have any advice on self-diagnosis and repair, please write 🙏

[irritated28]

Checked all the electrolytic capacitors on the power supply board - they are normal.

[Garp_senchau]

@irritated28, Welcome to HP Support Community,

Thank you for posting your query; I’m here to help by guiding you through steps to resolve this issue

Power Supply Check

Use a multimeter to measure the voltages from the power supply. Make sure they're stable and match the specs. Unstable voltages could cause flickering.

Firmware Update

Check if there’s a firmware update for the monitor on HP's website. If the problem started recently, try updating or doing a factory reset through the on-screen menu.

Test Different Cable/Source

Try a different HDMI/DisplayPort cable, or use a different device (like a different PC) to rule out input issues.

Also, I suggest you refer to this guide for further troubleshooting steps: HP Monitors - Display quality issues | HP® Support

I hope this helps.

Please feel free to reply here if you have any questions or if you need further clarification on any of the steps. 

Take care and have a good day. 

Did we resolve the issue? If yes, please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!

Regards,

[irritated28]

Thank you for your reply 🤗 Factory reset - no change. The problem is present even without HDMI/DS connection. Voltage is naturally unstable, since the defect disappears for a second when first turned on. There is a suspicious squeak on the step-down transformer.

Help please with: 

• find detailed documentation for monitor board electronics (I'll look for the name of the backlight controller)
• if it exists, with a circuit diagram (I'll try to find it by the backlight line)

I hope you can help 🙏

[Garp_senchau]

Hey @irritated28,

Thank you for your response

Could you please share the HP unit's serial number via private message!

Need help finding your product number? No worries! Check out this handy guide:

https://support.hp.com/in-en/document/ish_2039298-1862169-16 

To access your private messages, simply click the private message icon on the upper right corner of your HP Support Community profile, next to your profile name.

You can use this link as well:

Private Messages - HP Support Community

We're looking forward to helping you get back up and running!

Best regards,