I recently added a second desktop beneath my desk. The first one had dual monitors and space wouldn’t allow for more. I didn’t want to pay the high price for a dual monitor kvm switch, so I decided to try setting up dual monitors with two single monitor KVM switches.
I purchased two self-powered, PS/2 KVM switches with VGA connections. The switches weren’t powered by AC adapters or the VGA ports. On top of that, the signal to “switch” machines is actually sent by hardware… meaning, each machine needed its own signal to switch monitors. It took some careful bundling and routing of wires. My diagram to the left is the configuration that finally worked. I hit scroll lock twice for Machine 1, and scroll lock 6 times for Machine 2.
A dual monitor switch would have simplified things, but my solution cut the cost in half. I tried a number of KVM switch alternatives too: VNC software (UltraVNC, TightVNC, Remote Desktop), and Kavoom. Kavoom was a pretty good option, but without dual monitors plugged into both machines, the second desktop never retained its dual monitor settings.
Remote Desktop will let you pretend to have a dual monitor setup by using the /span switch from the command line. But all pop-up windows are centered, smack between the two monitors. I tested SplitView to fix that issue, and things were working pretty well. However, the deal-breaker with all of these alternatives is that I need to remote into multiple computers from both computers. You end up having to scroll to see the whole desktop within remote windows. And losing certain keyboard shortcuts is no fun either.
One final note on dual monitors: Windows 7 has built-in multi-monitor support in Remote Desktop, and the newest version of Remote Desktop is available for XP and Vista too. This means that if you have a multi-monitor setup on an XP/Vista/Windows 7, you can remotely connect to any Windows 7 machine, and regardless of how many monitors it physically has, your Windows 7 machine can match your multi-monitor setup. That rocks my socks. But my machines both run XP. Worth upgrading to Windows 7?

Hello Chip,
I want to attempt to make your design of the dual KVM sw. I need to better understand the cabling. Did you purchase mouse splitters?
Nope, I just used two KVM switches and the cords that came with them (a bundled cord, containing VGA, keyboard, and mouse cables).
This is just what I was looking for! Thanks! This is even better than 1/2 savings over a dual monitor KVM as the lower cost ones have spotty reviews so you have to go close to $200 and up to get a reliable one. Your solution only costs around $60 or less. I was thinking this could be done, and was contemplating how the hook ups would go when I found your site.
Glad you found the post useful, Soulfire. You’ll be happy to know that this setup is still working for me too… it’s been well over a year.
Hi Chip
This is just the configuration I am looking for.I am trying to understand the V1 and V2 on the machines. Are the connections to the kvm usb or ps2? Just looking for a little more clarification
Hi, ralltman! V1 and V2 are the VGA connections for the monitors. I think the little “K-V-M” box is confusing things. Let me know if you have more questions.