As far as I'm aware, Z chipsets are the only chipsets for intel that support overclocking.
This is correct. You will not be able to go above the Turbo speed with the H81.
I have the MSI Z87-G43 and it OC's to 4.6 GHz with ease. Great MB!http://www.msi.com/product/mb/Z87-G43.htmlhttp://www.newegg.com/Product/Product.aspx?Item=N82E16813130694