never heard about this one before, but i experience something similar on occasion, the Windows (7) color scheme, seemingly at random my computer wants to decrease the windows color scheme, supposely because windows sense that its running hot(?) i always pick the bottom option "keep current scheme and never ask this question again" (but it will ask again, count on that) its a typical mickey-soft thing and i suspect that what you experience is pretty much the same; Windows think theres something wrong and prompt you by going to desktop? I dont know, i read a lot up on my issue and it seems to be one of them weird "feats".
just thinking that maybe theres some odd bug in NA that havent really been optimized yet, a bug that cause some Windows parts to act weird, could be anything really, the games i/o, your laptop is getting kinda dusty and unoptimized NA take too many resources halting your performance due to the dust, i dont know.
when we get a faulty laptop in at work, 95% of the cases, faulty behaviour is due to dust and dirt blocking the cooling
craptops wasnt invented for gaming