Plugged in, not charging.

I spend a lot of time working from home, and I've invested quite a bit of time and money making sure that my home office space is as productive as possible. Part of getting that space as productive as possible. For me that means a combination of multiple screens, device placement, lighting and network topology. I've sometimes had my home office described by others as mission control.

Once you get a productive working environment you know immediately when something is not working correctly.

This week I attempted to change my screen configuration to free up a display for another purpose. My plan was to pull the screen from the MacBook Pro 15" which I fine is pretty good with just the built-in display. Unfortunately, because of the interface requirements (HDMI) I had to unplug one of the screens connected to my Surface Pro 3 and then shuffle the screen connected to the MacBook along so that I could maintain my three display configuration in my primary Windows environment.

Things worked out OK at first, I got the screens humming along, but a day later I noticed something. First, my Surface Pro 3 was making more noise than usual, the CPU seemed to be running slower, and the fan had spun up.

At first I didn't connect it with the screen change. I first double checked the connection to the dock, double checked for battery driver issues and tested with an external power pack. Eventually I noticed when I unplugged the recently added display that the PC resumed normal operation after a few moments.

My normal screen configuration used two identical 24" LG displays. The third display that I swapped in was also an LG, but lacked a HDMI interface, so I used a combination of a Mini-DisplayPort to HDMI converter and a HDMI to DVI cable to get the job done. After identifying the source of my woes, I swapped the displays back.

I'm not entirely sure what the issue is, but it could be that the alternative interface configuration draws more power from the Surface Pro 3. I'm actually surprised this is a problem when the device is plugged in, but perhaps it lifts the current draw on the power coming from the dock sufficiently for the battery charger to stop charging the battery.

Anyway - for now I'm back to my original productive configuration.