Iiyama ProLite B2280HS User Manual page 27

Adjust the Phase to correct horizontal wavy noise, flicker or blur in the zebra pattern.
NOTE
 In case the strong flicker or blurs remain on a part of the screen, repeat steps
and because the Clock may not be adjusted correctly. If the flicker or blurs still
remain, set the refresh rate of computer to low (60Hz) and repeat steps from
again.
 Adjust the H.Position after the Phase adjustment if the horizontal position moves
during the adjustment.
Adjust the Brightness and Color to get the desired picture after you complete the Clock
and Phase adjustments.
Put back your favorite wallpaper.
OPERATING THE MONITOR 23