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

[Stroller <stroller@stellar.eclipse.co.uk>]

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? 

The manufacturer of a KVM isn't going to be able to test it with all the 10,000 monitors available on the market today - not even 1% of them. They're happy if it works 99% of the time, and if you complain to them they'll say "oh, it must be a bug with that monitor" and maybe, eventually, give you a refund for the sake of a peaceful life. 

There are probably a handful of different KVM chips that are made by big manufacturers in Taiwan, and then sold by the 10,000 to other manufacturers, this time manufacturers of actual KVM units. These second tier manufacturers probably all wrap the KVM integrated circuits up in slightly different ways, using slightly different resistors and capacitors to interface with input and output. 

So in terms of your specific questions, I'm not able to answer very helpfully. I think you could waste a lot of time trying to get these answers, whereas you could swap in a specific model and try it in a matter of minutes - and that way you'd know for sure.

Stroller.