I have however seen LCD monitors behave significantly different
depending on refresh rate. Entire areas were blury, but everything was
fine when I switched to another refresh rate (60Hz -> 75Hz if I remember
correctly).
I have never owned an LCD/LED monitor that one could change that
setting on. And I've owned quite a few.
Not in any OS, Debian, Ubuntu, SuSE, Mandriva, Fedora, Arch, Gentoo,
Slackware, PCBSD, FreeBSD, Haiku, Windows in any form or version, nv
driver, Nvidia driver, Nouveau driver VESA, Matrox, Cirrus logic,
Intel driver, Bare metal or native or Virtualbox or VMWare or Xen or
QEMU, any version of Xfree86, X.org, Wayland, KDE3, KDE4, GNOME 2,
GNOME 3, MATE, Cinnamon, XFCE, Open box, bare X, LXDE, Unity,
Moblin, LightDM, KDM,GDM, XDM.