I just did the exact same mod, after which i stumbled uppon your post :)
For me it wasen't so much the temperature, but more the thermal throttling when playing Youtube 1080p 60FPS. It would do it fine for a few minutes, but it would slowly clock the CPU down to about 0.7Ghz to a point where the video would be constantly loading. I have a few of these Atoms, and they all have their thermal issues, not so much when the CPU has high loads, more when the GPU is active (in my usecase videodecoding). That seems to generate a lot more heat, and most of the time the thermal solution is re