Problem connecting KVM Switch

[eggman9000]

I am trying to connect 2 computers to a KVM Switch.  The KVM is a Belkin Omniview Pro3.  Computer 1 is an IBM ThinkCentre Desktop and Computer 2 is an HP Elitebook 8460p using a docking station.  When Computer 1 is connected to the KVM is operates just fine.  I am running Computer 2 with a docking station and also using extended desktop.  the monitor connected to the KVM is a HP LA1951g. (as the primary monitor)

The problem arises when connecting the Elitebook 8460p.  When this is connected to the KVM, the built-in display of the laptop and the external monitor seem to be fighting each other.  The settings will automatically toggle between extended desktop on the external monitor and a single display on the laptop screen.  This "automatic switching" will happen every couple of seconds and will continue like that until you switch back to Computer 1.

Has anyone out there encountered such an issue and subsequently found a solution?  I have tried many different things and still have the same issue.  Belkin support is passing the buck and says it is an issue with the VGA port.

Please help!!!

Kind regards.

[Cloud_Strider]

Out of curiosity, does the issue persist if you connect the monitor directly to the notebook rather than through a docking station? 

Does this happen if the HP is connected directly to the monitor bypassing the KVM switch?

If you swap the VGA cable between computer 1 and computer 2, does the issue persist?

The answers to the above questions may help isolate the issue.

What model is the dock? 

I take it this is through using the VGA port as most KVM switches have just VGA. 

[eggman9000]

The problem does persist when connecting the monitor directly to the laptop when using the KVM.  It does not happen when you connect the monitor and by-pass the KVM switch.  Swapping the cables between the two computers does not resolve the issue either.

From what I can see the docking station just says PR Docking station.  It is HP and came with the Laptop.  This is connected through the VGA, yes.

[Cloud_Strider]

The fact that the issue does not happen when the KVM is removed seems to indicate it is the VGA port on the KVM switch. I know that you already contacted Belkin, but I don't think the KVM is ruled out at this point. 

I would like to try a different configuration to verify that is the issue.  The previous scenario was swapping the cables with the systems still connecting to the same ports on the KVM switch.  In this setup, I would like to switch what ports the systems are connecting to on the KVM so that the IBM connects to the VGA port the HP was connected to and the HP connects to the port the IBM is connected to. 

Based on the previous result of the issue not being present without the KVM in the equation, I suspect the issue will then happen with the IBM and the HP will be fine. 

Let me know what happens. 

[eggman9000]

The KVM switch that I have has one cable that allows you to connect 2 computers to it.  It is an 8 port switch, but on the switch itself is only 4 ports.  Computers 1 and 2 would connect to Port 1, computers 3 and 4 to Port 2, etc.  The cable splits and you have a VGA and USB connection at either end to connect to the respective computers.  I have had the computers set up on separate ports,  different ports  you name.  I have connected it just about anyway you can think of.  The issue still remains with the the HP.  It is exaserbating to say the least.

My apprehension is I don't want to replace the cables or the switch until I get a definitive answer to the problem.  I don't want to get a new KVM just to have the same problem with the new one.

[Cloud_Strider]

I understand.  I wouldn't expect anyone to run out and buy a new piece of equipment without some confirmation that it is the issue.  Especially with this KVM switch being the price it is.  If the unit is under warranty, I would imagine this would be covered. 

The issue is not present when the KVM is removed from the picture.  To me, that says that the issue is not within the HP or the dock itself or it would be present when it's connected directly to the monitor without the KVM switch. 

I will see what other options I can find at this point.

 I take it this is the cable in use.

When the cable was swapped around earlier, was just the ends of the same cable moved from one unit to the other or was a completely different cable used?  If it was just the different ends, then the cable itself wouldn't be ruled out at this point.  The only way to rule out the cable would be to use a different cable altogether.  let me know if it was the ends that were swapped around or if a different cable was used.

[eggman9000]

I have 2 cables here and they have both been used to connect the switch to the PC's.  Still have the same issue.  So I am pretty confident that it is not the cables either. I have seen on other boards that it might be a driver issue.  I have checked the Intel site, and it says that the driver for my HP is a non-standard driver provided for as enterprise solution.  Possibility lies that it could be the graphics driver, but also if the driver is updated it could cause other issues.  Then I havew swapped 1 problem for another.

[Cloud_Strider]

One thought is to ensure that the notebook is not exceeding the maximum resolution 1920 x 1440 of the KVM switch.  This is probably not the case, but wanted to mention to not overlook anything. 

Verify that the notebook is using a supported refresh rate for the monitor.  Most monitors use 60 Hz and anything over this could cause strange behavior as this.  It has been quite sometime since I have seen a refresh rate issue, but anything is possible. 

Regarding the driver, you should be able to create a restore point before updating the driver.  Should anything not go as planned, you could then restore to that restore point.  I will note that I do not know what is installed on the notebook and whether or not they would be impacted by a system restore going back just a few minutes.  Personally, I have not had a program affected by a system restore. 

[KVM_4_PRO]

The issues are triggered by the KVM switch which did not pass correct and timing EDID information communication between amoung the display monitor, docking station, KVM switch and the connected PCs.  

You can try to but an "EDID Emulator" between the docking station and the KVM switch of the connected PC. 

The EDID emulator can provide full-time EDID info and feeding the correct EDID  to the connected systems.