Howdy,
On my system, the icons and fonts in the KDE desktop were too small. My original resolution was 75 dpi. Adjusting the resolution to 120 dpi is just about right. Here's how.
You will need to add:
DisplaySize X Y
to /etc/X11/xorg.conf under the "Monitor" section where:
X = (monitor-width-pixels/desired-dpi)*25.4
Y = (monitor-height-pixels/desired-dpi)*25.4
In my case:
X = (1920/120)*25.4 = 406
Y = (1080/120)*25.4 = 229
so my DisplaySize line is:
DisplaySize 406 229
HTH,
Roy