On Sun, Jan 22, 2012 at 10:07 AM, G.Wolfe Woodbury <redwo...@gmail.com> wrote: > On 01/22/2012 12:42 PM, Mark Knecht wrote: >> >> I played a bit with get-edid | parse-edid. Logically that stuff even >> working says the VGA monitor cable is bidirectional. I started wondering if >> the KVM messes up the data coming back, or what else might be going on. >> Thanks for the ideas, Mark > > Many of the cheap KVM models do, indeed, mess up the EDID data coming from > the monitor. I suspect that this is from old design specs that have too > much pull-up/pull-down on the EDID lead since the boxen haven been > re-engineered for newer, higher resolution and higher speed monitors. > > I have had problems specifically with the BELKIN KVMs. > > It may also be that the video drivers for Linux are just enough different > (necessarily) from the MSFT drivers to not reliably sense the EDID return > signals. > > I did as others suggested and tried several until I found one that worked. > Sometimes a slightly different model/serial/part no KVM from the same > manufacturer would/wouldn't work. > > -- > G.Wolfe Woodbury > redwo...@gmail.com > >
Thanks. Sounds about like what was going on at his place and it's a reasonable evaluation potentially. I guess I could have made it a bit more clear early on - I'm not looking to solve anything here and I'm not buying KVMs. I was just curious as to the root cause of the problem. I've seen it discussed periodically for over a decade but never any strong analysis of why it happens. It's not a huge problem to the community. Cheers, Mark
