I booted the demo but got a call before I could hop into the action. During my call I noticed my computer receiving permission for lift-off. At least that's what I heard. My GPU was constantly hitting 90°C and ~400 FPS idling in the menu.

Once you start playing the game, or after enabling VSync, everything's fine, but I shouldn't strain my GPU until I get there.

EDIT: GOG didn't like my .png, so here's the .jpg