Dell XPS 14 Overheating

My Dell XPS 14 (Core i5, nVidia 420M, 6 GB RAM) is overheating terribly when playing Skyrim, and now Mass Effect 3. After about 15 minutes of gameplay in either, the sound slows down (sounds like a bad acid trip), the framerate drops to about 5 spf (yes, seconds per frame, not frames per second) until I close the game out. This happens when I am playing on a hard surface, so that is not the issue. The only time I have ever had it happen with any other game was when playing on a bed with the blanket blocking the air output, but with ME3 and Skyrim, I get this issue every 15 minutes on a hard surface, even with the graphics turned all the way down. I have the latest nVidia drivers installed. As it doesn't happen in any other games, is there a chance that there is something software related here? I know the first response is going to be to get a cooling pad, but I only ever use this computer for gaming when I am out and about (I have a beastly desktop rig at home), so the cooling pad is not really a solution for me.