its up to you
but if you got a k series cpu you could overclock it
are you using the stock cooler?
my llc only needs to be on standard up to about 4.5ghz--though my 2600k will be a little different to a 3570k
if llc is on auto set it to one of the lower options
or just leave as is and up your multiplier to overclock it
just keep an eye on cpu temps with real temp or similar