Re: [gentoo-user] KVM problems - anyone know _why_ it happens?

[Michael Mol <mikemol@gmail.com>]

On Sun, Jan 22, 2012 at 12:47 PM, Stroller
<stroller@stellar.eclipse.co.uk> wrote:
>
> On 22 January 2012, at 15:54, Mark Knecht wrote:
>> ...
>> Basically, I looked around in Google for anyone that had real info
>> about why this problem occurs, couldn't find any that made sense, and
>> am wondering how to choose a KVM that's going to work out of the box
>> short of asking for model numbers, etc.
>
> For all you've written, I'm afraid the best answer you're likely to get it "buy a KVM you can return" (or buy secondhand at a price you can resell without loss).
>
> Video resolutions / refresh rates / timing / &c is a bit of a black art. What the heck is a modeline?

A modeline is a one-liner way of representing a display driver mode. I
always preferred the block form; it's far more readable. It's been
almost a decade since I've written one, though. Haven't really needed
to since XFree86 4 came out.

I don't remember all of the bits of information in it, but here are
some of the highlights:
* Vertical refresh rate (in kHz): how rapidly the CRT's electron beam
crosses the screen horizontally.
* Horizontal refresh rate (in Hz): how rapidly the CRT's electron beam
crosses the screen vertically.
* Some horizontal and vertical overdraw values I don't remember the
specifics of, but it amounts to realizing that the electron beam is
active past the bezel of your monitor.

"xvidtune", by the way, was an awesome way to do live testing and
configuration of these values, and it would emit a modeline for you
when you asked it.

-- 
:wq