The asrock extreme 3 is not that good board but the extreme 4 is much better as it has much better vfm and better power phase design.
If u looking to get the extreme 3, then within that price range,grab a MSI 970A-G46.
IT would be fine but be aware of the heat and today u are not O.C ing but tomorrow u would.who can say. Get the extreme 4, i don't think that there is a huge price diff. between the two, so why not get the better?