Symptoms
- Screen has a subtle shimmer, especially on fine patterns or thin lines
- Effect is more visible on certain backgrounds like checkerboards or thin text
- Shimmer changes with scrolling speed
- Feels similar to a moiré or watery effect
Likely causes
- CommonNon-native resolution causing scaling artifactsScaling a lower or higher resolution to fit the panel can create shimmering moiré patterns on fine detail.
- CommonRefresh rate mismatch or variable refresh rate instabilityAn unstable refresh rate, especially with adaptive sync enabled, can create a subtle vibrating look.
- PossibleVideo cable or port interferenceA marginal signal can introduce subtle visual noise that looks like shimmer.
- PossibleFont rendering/anti-aliasing settingsCertain font smoothing settings interacting with scaling can create a shimmering look on text specifically.
What to do
- Set the display resolution to the monitor's native resolution rather than a scaled one.
- Confirm the refresh rate is set to a value the monitor explicitly supports, and try disabling adaptive sync temporarily to see if the shimmer changes.
- Try a different cable, especially switching between HDMI and DisplayPort if both are available.
- Adjust font smoothing (ClearType on Windows) using the built-in tuning tool.
- Update the graphics driver, since scaling and refresh rate handling improve with driver updates.
- Compare the shimmer effect at 100% scaling versus other percentages, since this can be a scaling-algorithm artifact more than a hardware issue.
Tools and parts
- None
When to call a pro
This is generally a settings or cable issue; if shimmering persists at native resolution with a known-good cable, have a technician check the monitor's video processing board.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.