Just scanned this thread quickly, and as no-one has mentioned it then I will add:
If your system is very low on memory (physical RAM) then paging will occur even due to just operating system processes (there need not be a user installed application actually doing anything).
Ok your PC is new so I would expect that a good amount of RAM is there - did it all get seen at memory-check time when the bios starts at boot up? A duff memory card in a new PC would not be unheard of and would cause lots of paging.
You don't always get an boot-up error when a memory card is not seen/fails, just less memory is displayed and who checks that every reboot?