Compaq/Avocent KVM switch dead
 

Hi everyone,

I have an 8-port KVM switch (A Compaq EO1004C) which has suddenly died
on me. When I switch it on the LEDs on the attached keyboard blink
(which indicates the keyboard successfully received a 'reset' command)
but that's as far as it gets.

I checked its power supply and it seems fine (+5V, +12V and -5V all
okay) so the problem is on the main board - which is just a couple of
chips and masses of surface-mount capacitors and resistors connected to
each of the sockets.

I've got no idea where to start looking to figure out what went wrong.
Does anyone have any suggestions as to how one might go about checking
this sort of equipment?

Annoyingly enough there are a few points on the board labelled as TP7,
TP8, etc. but Avocent have long since thrown all their docs away, and
Compaq probably never had them to begin with.

Any advice would be greatly appreciated!

Thanks,
Adam.