CPU Throttling when display set to 'Second Screen Only'

[gcinini]

Got an interesting behavior on my Surface Pro 3 running W10 Enterprise Build 14361.rs1: a few seconds after I connect a DisplayLink dock and I have my screen set as 'Project: Second Screen Only' to have my screen on the monitor connected to the dock thru the VGA connector, my CPU throttles down to 30%, and consequently system slows down to a crawl becoming unresponsive every few seconds.
If I change the display*setting to Extend, Duplicate, or*PC Screen Only, the throttling goes away. As soon as I set it back to 'Second Screen Only'*the CPU throttling comes back.

It only happens when connected thru the DisplayLink dock. I tested with the displayport dongle directly to the same monitor and the problem did not occur.

I just installed the DisplayLink 8 beta driver from their site and still have the same problem. Probably a bug somewhere in the video driver interacting with the DisplayLink driver
Build# : 14361.RS1_RELEASE

Tried the same setting with my secondary Surface Pro 3 with build 14376.rs1 and the same behavior occurred. I uninstalled and reinstalled the DisplayLink driver and no change.
Installed updated video chipset driver from Intel, no change.