Go into your /etc/X11 directory, or it's equivalent in feather linux, and edit your xorg.conf or xf86config file, or whatever it is, and change the horizontal and vertical refresh rates to whatever your monitor supports.
This is form my xorg.conf file in ubuntu:
Code:
Section "Monitor"
Identifier "Generic Monitor"
# Option "DPMS"
HorizSync 31-93
VertRefresh 50-160
EndSection