So I'm playing Deus Ex Human Revelution at full screen, and near the end of the game it randomly minimizes to the desktop. I thought it might just be the game, but later on, playing another game, it does the same. Now it does it every 10 to 20 minutes. I don't have any programs running in the background and my CPU and graphics card temperatures never go to high. This only recently started, but apart from Steam, I don't remember installing any new applications.
PS.: When it minimizes, there are no messages displayed or anything that can indicate that another program might be requesting to be on top. What could be the cause of this?