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Why some Windows process stay writing on disk even on system idle?
When I don't use my computer (idle), I start to hear my SATA disk very well. But when I use the computer, disk isn't so loud. It's funny but my computer is louder when I don't use it at all. Also "System idle process" is using more CPU on idle.
Question: what Windows 7 is doing when I don't use computer.
Note: no applications running in background.