Gentoo Archives: gentoo-user

From: Greg Turner <gmt@×××××.us>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] multiple monitor refresh rates and broken brains (was: fonts and bad eyes)
Date: Sat, 17 May 2014 19:38:15
On Sat, May 17, 2014 at 4:21 AM, David Haller <gentoo@×××××××.de> wrote:

> Oh, and _very_ importantly: get a _GOOD_ matt monitor if you haven't > yet. >
Apologies, David, for hijacking your really good question-thread, which I'm also very eager to hear people's answers to. But, this reminds me of something I've been pondering lately... I think maybe refresh-rate discrepancies are subtly evil in multi-monitor setups. When I look at my 59.9 kHz apple cinema next to my 60 kHz POS Dell throwaway monitor, something spooky clearly happens in my brain -- if I get up close and look carefully, the pixels seem to rather dramatically "swim" near the bezels between the two monitors, in a way that reminds me of a migraine prodrome (perhaps because, to some degree, that's exactly what I'm inducing in my brain, by exposing it to high-frequency polyharmonic interference (presumably, there's a >0.5 MHz harmonic between those two displays, no wonder my brain doesn't like it!). In practice, I don't seem to have had any huge problem from this (and I'm going to get rid of that crappy Dell soon, anyhow) but I have heard reports from people claiming this type of thing caused eye fatigue and headaches. My semi-baseless theory is that, so long as the remainders of the greatest common multiples of your various monitors' refresh-rates form nice clean ratios like 1:2, 2:3, etc, you probably won't fry your wetware input circuitry looking at them. However, if, as above, there are ugly harmonics, I suspect it might be pretty bad for some people. If, like me, you're too cheap for the 100% solution of buying identical monitors, maybe just try to ensure everything you buy supports standard 60kHz standard modes, or even go read the 1990's-era ModeLine authoring FAQ's and attempt to actually understand the problem and fix it, if you're feeling ambitious :) Anyhow... we now return to our regularly schedule programming... -gmt