KVM Switcher

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I have a 4-port KVM switcher which I use with a variety of computers
with various operating systems (Win XP, Mac, Linux).  I have 2
machines which exhibit the same problem: The switcher locks on to the
signal from the computer (solid led) but I get no video, as if the
machine were powered off.  One of these mainboards is a Gigabyte
GA-6BXDS and the other is a MTechnology Stallion ATX-M668.  I have
tested both machines with different video cards and power supplies to
no avail.

Any suggestions are appreciated.


Re: KVM Switcher

"J" wrote ...
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Did you isolate the problem from the KVM? i.e. hook up the computers
directly to monitor.

Re: KVM Switcher

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there is the possibility that the KVM Switch is bad!

test the monitor to make sure it isn't bad

do you get any keyboard or mouse?  I know you have no video. But one
possible check is perhaps if the kvm has a hotkey to switch from one
comp to another.
If the KVM indicates which comp you are on, then using the hotkey
should move the led too.

Another possible check, is, well, I used to use a comp with no monitor
in some situations, in the days of msdos.

see if after typing commands, you get any activity on the computer
indicating that it heard you.

boot up with an msdos boot disk  / win98 boot disk.

best to make the boot disk very lightweight so we're sure you get to a
command prompt. So leave IO.SYS COMMAND.COM, (I don't think you need
MSDOS.SYS on a floppy, but you could keep it there anyway). Delete all
the other files on the floppy, including a:\autoexec.bat and a:

Then when you think/know you'd be at a command prompt
dir a: <ENTER>

and see if this gets a light "/" sound from your floppy drive,
indicating that the computer is responding.

You could do
break=on <ENTER>
dir /s <ENTER>
see if that gets hard drive activity, then do CTRL-C to get cancel the
dir /s.
though that'd work more if you've got a big FAT32 hard drive. Not an
NTFS one.

if you have a light for the hard drive you can dream up things to type
to see if you get activity.. related to entering commands on the


A far neater idea is , to get a VGA Splitter Cable. It plugs into the
back of the comp, vga connector and gives you 2 vga sockets instead of
plug one into the kvm and the other plug a monitor into it.

type into the keyboard connected to the kvm, see if it appears on the
screen of the monitor that's connected directly to the computer.

Actually, you don't even need a VGA splitter cable to do it.

Choose not to plug the computer's VGA into the KVM. Plug keyboard and
mouse into the KVM, and plug a regular monitor into the computer.

See if typing on the keyboard gets anything..

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from mouse or keyboard. But none from VGA, so VGA is always optional -
I don't even know if VGA has any power lines. (cat5 doesn't, ps2 and
usb do ..)

Re: KVM Switcher

On 18 Apr, 21:33, "jameshanle...@yahoo.co.uk" <snip>

err, I think my best suggestion was actually what jeff said ;-)

to test what's happening with the kvm

keep each comp's keyb and mouse ports connected to kvm.
but not vga.
plug a monitor  into a comp , tell the kvm to use that comp(there may
be a button on the kvm), and see if it responds to keyboard activity
(thet keyboard is going through that port of the kvm)..

The hotkey is another easy test

the msdos idea I suggested is unnecessary.

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