I got exactly the same problem with you. Even the 0.4 Ghz
Before I moved into a room with no air conditioner 2 weeks ago, the throttle wouldn't happen.
And the temperature of my new house always stays at about 30 ℃ (or higher)
And I noticed that while charging, the temperature is higher, and the throttle will more likely happen.
Heya,
I have been having the same problem. I tried to play a few games (different games requiring low and high performances), but the laptop CPU clock drops down to around 0.5 Ghz. Lowering the settings to even the lowest end doesn't change anything. I have the highest available model of surface book 2 15 inch. The laptop was fine till a month ago and then this started happening. I am not sure if it was an update that messed it up. Does a factory reset fix it?
One thing i noticed is that when I am in game, the fans hardly work (or very silent) and when the lagging starts and I go to desktop, then the fans turn on running fast and loud..Going back to the game seems to fix the problem for 20-30 seconds before which I get the problem again. So I am assuming that it is a heating problem where the laptop is not able to turn on adequate cooling process unless I exit the game.
This is a £ 3000 device and its breaking my heart that I cant play any game even with such high end components!
Please help someone
Razik