It depends on what you do with your system as to how often
you should run chkdsk and defrag. I defrag weekly and run
chkdsk at least once every couple of months. I never let
my defrag level get over %6 and checking it takes seconds
to see if it's needed. I placed a shortcut to defrag on
the desktop.go>start\my computer and right click your main
drive(usually C:\) then click properties\tool tab. Keep
smiling.