another really really common thing-
is that people run multiple monitors out of a computer at different sizes and refresh rates-
sometimes they run a triple head and a single screen-
with this - the refresh rates are different to each monitor
vga/dvi have different refresh rates at different sizes-
for 60Hz its somewhere between 60.04 and 59.95
dvi and vga are not constant frame rates at different screen sizes.
then they do video input - at 25 or 29.97 -
an enormous number of possibilities - i try to do the best possible thing for these complex scenarios.
i found a vga frame rate calculator at :
http://www.tkk.fi/Misc/Electronics/f...2rgb/calc.html