Sunday, March 11, 2018

Use Thinkpad x240 with two monitors

I'm using a company-issued Thinkpad X240 (quad core, 8 GB RAM, 65W power supply (I think it is officially considered to be 70W) and I am doing a lot of work at home on the weekends. At work it connects via docking station to a single 32-inch monitor (nice one, too!). At home on the weekends, I want to use my dual 27-inch ASUS monitors and my KVM.

This has been a rough couple of days because my KVM  (Keyboard Video Mouse switch) supports dual DVI ports, and the Thinkpad X240 only has a mini display port and a VGA output. I tried a Dual Monitor Docking Station by Plugable (UD-3900), but because this is company issued, I cannot install the drivers to use it (back to Amazon it goes).

I got it working (finally) by mostly bypassing the KVM and wiring directly to the backs of my monitors, but then the thing gets buggy after it goes to sleep sometimes the dual monitors don't come back. After some trial and error (and some bourbon) I finally sorted out how to get it working consistently.

Required Cables:

  • VGA cable
  • Mini displayport to (regular) display port cable
  • USB-A to USB-B (see graphic) cable
    (FYI: Type A is the "standard" USB cable)

Even though I have to manually connect the monitors (the KVM doesn't do a great job of mixing a digital and an analog signal – I think if this were hooked up here every day I could figure a way to get it to work, but since I only bring the company laptop home on weekends, it's not worth the extra time it would take to sort out). However, I do want to use my keyboard and mouse, which is why I'm routing that signal through the KVM.

Connecting the monitors and the KVM
With both the laptop AND monitors powered down, make the following connections.

Plug USB-B into back of KVM
Plug USB-A into laptop
Plug large end into Monitor 1
Plug small end into laptop
Plug into Monitor 2
I cannot stress this enough: DO NOT PLUG THE VGA CABLE INTO THE LAPTOP!

  1. Turn on the laptop. Let it boot up completely (be patient). I wait until everything has stopped spinning about and launch Outlook. I let it check my mail. When I'm certain that it has completely booted up...
  2. Turn on both monitors. Monitor 1 should automatically start working (i.e. get the signal and you can use it).
  3. Plug the VGA cable into the laptop. It should also start working. If not, check out the "Alternate Method" I describe below.

This is the method I've been using for awhile now. If this assignment continues with weekend work, I may look into another method of getting it to work (this one is annoying because sometimes I step away for a break and come back to find it has "lost" one or both monitors (usually powering off monitor 1 will bring that one back).
BTW: You want to use the VGA on your second screen because the Displayport connection (which also sends sound) is digital and will be a bit crisper and cleaner than the VGA signal. 

I can't swear this method will work for you, so good luck!

I only use this if the monitors aren’t automatically detected (and you may have to do this the first time you try connecting to the external monitors).
With the monitors connected to the laptop and powered on, type the WINDOWS KEY + P. (Yes, the button to launch your Start menu, plus the letter P.) In Win 7, 8 & 10 this will launch a menu where you can pick the following:
  • Disconnect Projector
  • Duplicate
  • Extend
  • Projector Only
Select "extend" and then Monitor 1 will receive the signal and should work. If the laptop doesn’t see the monitor, then turn the monitor off and then power it on again. I think it has some kind of “handshake” signal when it powers up that the laptop needs to see. 

No comments:

Post a Comment