Monitor refresh rate query

Noel Chiappa jnc at
Fri Jun 17 14:27:32 CDT 2016

    > From: Peter Corlett

Hi, thanks for helping me out here!

    > Both are correct. There are 44 (rounded) frames per second, and 87
    > (rounded) fields per second.

"fields per second" refers to interlaced displays, right? So the vertical
retrace frequence there is the 87 Hz number (since you get a vertical retrace
after only 768/2 lines are displayed). Or am I confused?

Although if I'm right so far, I'm puzzled as to how one could drive both
interlaced and non-interlaced monitors off the same video signal - wouldn't
the interlaced one need a video signal which has 'odd lines, then a vertical
retrace, then even lines, then a vertical retrace'?

Anyway, so which one is the one which is the number to look at when
considering if the refresh rate is so high it might be dangerous to an old
CRT monitor? I would assume it's the 'fields per second', since that's the
frequency of the vertical retrace?

E.g. my HP M50 manual says "Setting the screen resolution/refresh rate
combination higher than 1024x768 at 60 Hz can damage the display." Even
though the same document lists the vertical frequency range as "50-100 Hz"!


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