In article ,
T i m wrote:
On Sat, 29 Aug 2020 04:47:09 -0000 (UTC), jon wrote:

snip

I used a KVM switch about ten years a to select any one of three computers
for the monitor.

I have done similar with a two way Aten and now 3 off 4 way. ;-)

That was all superseded long ago when I got an Asus 27"
monitor with multiple inputs. I only have two computers computers
connected now and I do the switching directly on the monitor. The cabling
is very much neater.

Yeahbut don't you have to pick up the remote or press the input button
on the monitor itself (no so easy if it's out of arms reach), as
opposed to just hitting 'ScrlLk-ScrlLk-1-4'?

Quite. Both my monitors have 'soft touch' input selection. Neither is as
easy to use as a couple of keyboard strokes.

The problem Dave has been seeing is as has been mentioned elsewhere
and likely a clash / lack / contradiction of information going back to
the PC from either the KVM switch and the computers themselves.

The more 'automagic' the machine / switch / OS the more likely it will
be to suffer this sort of thing.

I have similar between a 40" TV VGA input and a 4 port VGA KVM and a
W10 ITX PC I built that has both VGA and HDMI outputs. W10 gets very
confused [1], often only outputting on the disconnected HDMI port and
not the VGA.

Only using the video card DVI output on the PC.

Swap to a smaller TV with VGA and it all works fine.

Not all PC's on that switch support HDMI (ironically the two RPi's do
g) so I keep to VGA as the L.C.D.

Cheers, T i m

[1] On VGA through the KVM to 40" TV, you get the PC BIOS splash
screen, the W10 booting logo and then nothing (as the video output has
switched from VGA to HDMI).

The old PC worked just fine with the same monitor and KVM switch. With the
proviso that if you didn't switch to it before waking it up, it selected
the wrong resolution, but easily corrected. With this one, the only way to
get back to the correct resolution is with a re-boot.

--
*We have enough youth, how about a fountain of Smart?

Dave Plowman London SW
To e-mail, change noise into sound.