How to connect two external monitors to your Mac laptop

In my own work in software development I have found that multiple monitors connected to my laptop computer help improve my productivity as well as my ergonomic health. For example, if I need to compare the contents of two large spreadsheets, I can put them side by side on two different monitors; or I can dedicate one monitor for browsing, another for email or instant messaging, and the third one for command line shell. As a Web search with the query “coding productivity multiple monitors” returns, it seems there is some evidence on the benefits observed or advocated by others too.

At my work with Vida Health, I use a MacBook Pro laptop with a 15-inch display. Here I will present how I connected two additional monitors to my laptop. There are lots of resources on the Web on this topic but I have found many of them confusing so I have decided to write a hopefully simpler recipe of my own, which did work for me. Also this is my first post on Medium so I felt that starting with a simple “how to” article is a good move. I hope you will find this article useful.

My (ergonomic) setup includes the following components (in addition to a height-adjustable desk and a multi-point adjustable chair):

  1. A MacBook Pro laptop: I used a new one as well as a three-year old one in this setup. Both worked fine.
  2. A vertical mouse: I prefer a wired one from Evoluent for the left hand. A regular mouse, wired, wireless, or from a different brand, also seems to work fine.
  3. A split keyboard: I prefer a wired one from Goldtouch. A regular keyboard, wired, wireless, or from a different brand, also seems to work fine.
  4. Two external monitors: Different sizes and brands seem possible here; my monitors are 24-inch ones from Dell.
  5. A Belkin Thunderbolt Express dock: A dock like this one is key to ensuring that you have enough ports to make all the connections. It also allows you to use a single connector to connect your laptop to all its accessories.
  6. A USB to DVI adapter: This is used to connect one of the monitors from its DVI port to a USB port on the dock. My adapter is from StarTech, called the USB to DVI external video card adapter for Mac.
  7. A Thunderbolt cable: This is used to connect the dock to my laptop. Make sure you get one long enough; mine is two feet long.
  8. A Thunderbolt to DVI adapter: This is used to connect the other monitor from its DVI port to a Thunderbolt port on the dock.

Hope it is clear but it will not hurt repeating: I specify some brands above to clarify exactly what has worked for me rather than promoting those brands. It is likely that similar components by other brands can also work in a similar setup.

I arranged the monitors and my laptop as shown below. This arrangement allows me a natural circular motion in clockwise or vice versa direction to visit all three of my monitors easily.

The following picture illustrates how the dock connects the two monitors to my laptop together with my keyboard and mouse.

So far I have witnessed two potential issues with this setup:

  1. When I connect the laptop to the dock using the Thunderbolt cable, the keyboard is sometimes unresponsive. My solution is to disconnect and reconnect the keyboard cable to the USB port on the dock.
  2. When I disconnect may laptop from the dock, my laptop sometimes seems to think that it still has the monitors connected or the display size is larger than its own display size. To prevent this issue, a cumbersome but effective method is to minimize all windows to my laptop display before disconnecting my laptop from the dock.

Both of these issues are rare enough that they do not bother me at all. I do not know the exact reason for these issues but it seems that they have something to do with the dock. There are some discussions on the second issue on the Web.

That is all.

Acknowledgments: My initial setup was done with the help of the IT team at Turn, where I worked for 4.5 years until the end of 2015.