Many Intel made mobos simply will not overclock at all. Some will overclock but only a couple of 100 megahertz. To me that is small. 4.5GHz is not small to me but I don't know if any Intel made mobos go that high. Maybe they are finally getting with the times and allowing for better overclocks in their Bios? Like I was saying Intel is not known for high overclocking mobos but they are known for their mobos to be very stable and reliable.
Like Gevorg said if you want a serious overclocking mobo, ASUS, Gigabyte, AsRock, MSI and etc., make them and better.