I have wavy horizontal lines on monitor display

[Dbaino]

Monitor works fine on another PC 

[Riddle_Decipher]

@Dbaino Note: Please ensure the complete product name/number for a quicker response from the community, as we need to know what we are dealing with to provide an accurate solution: Click here for steps on finding the information we need!

Remember: Do not share any of your personal information such as serial, phone number, email ID, etc.

Meanwhile, I have a few more steps that should help: 

Since this is not a monitor issue, as confirmed by you, let's perform a power reset (no data loss) using these steps: Click here, proceed to next step if this works

Attempt to run a test from the HP hardware diagnostic tool, using this link: Click here for details.

If the issue appears on the diagnostics, it could again, determine a hardware failure,

If they don't appear on bios & the hardware tests passed: please update the BIOS & Chip-set drivers from the HP website using this link: Click here

if the issue persists, reinstall windows using the recovery partition or the recovery media to fix the issue,
use this link for details on performing the recovery: Click here

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