Usually this think is to do automatic overclock. If you want to do it yourself (which is always better) you should have it at manual, unless this thing is not for auto overclock (which I doubt)
Edit
I just read a bit about it, and many says that it should be on auto. I don't understand why, but.. try auto
My first build:
Storage: Kingston SSD Now V200+ 120G and WD Caviar Blue HDD 500 G
Processing Units: i5-3570k @ 3.8 Ghz cooled by 212 Evo and MSI Twin Frozr 3, R7850 @ 900, 1200
Mobo, Ram, PSU Gigabyte Z77-D3H and G.Skill ripjaw 2x 4G with XFX 550w
If I am unreadable, its not because I hate grammar, its because Im french-canadian
It has been on auto since yesterday. I was able to get 4.5 on 1.3v with temps in mid-high 70s. Wasnt able to get 1:1 cache cpu ratio so I brought it down to 4.2 and memory frequency is at 1400. It has been stable for 10 hours now. I am gonna wait 2 more hours and stop testing.