Question Stuck at 144 hz on 240 hz monitor

[lisbono2001]

I bought a Lenovo monitor model Y27gq-25 which is 2k (1440p) display 240 hz monitor. It's fine for the first few days but after that it stuck at 144hz.
So I decided to send it to the retailer store where I bought it from for them to diagnose the issue. But when they test it, it seem fine so they send it back to me with the result.
At that day I can use 240hz for just a day then it went back to stuck at 144hz again!

What I tried

• Reset monitor settings
• Try to change refresh rate in display adapter -> no 240hz option
• Change resolution to FHD -> 240hz option still not shown up
• Create custom resolution in Nvidia control panel to 2k 240hz -> all screen muddy so I revert it back
• Install the monitor's driver
• Update GPU driver to latest version
• Rollback GPU driver to older versions
• Change DP cable, Change HDMI cable
• Change monitor's power supply
• Change GPU (from 1070 to 3070)
• Update Windows (from 10 to 11)
• etc.

If you guys have any idea how to fix this please leave a comment, thank you very much.

PS. I live in Thailand which warranty of products are suck.

 

[Lutfij]

Welcome to the forums, newcomer!

When you state rolling back/reinstalling your GPU drivers, did you do so with the latest from Nvidia's support site? You're advised to use DDU to rid your prior GPU drivers every time you migrate to a new or old GPU driver version or even replacing a GPU in your build.

Make and model of your motherboard? BIOS version for said motherboard? Where did you source the installers for your OS? What OS are you on at the time of writing? Make and model of your PSU and it's age?