AMD specifically can be overclocked (without motherboard settings) and as well they have been sold in market (though was fraud), peopple use to buy 1500+ CPU's and there are micro bridges on AMD Chipset, by joining them, they can be over clocked. and they join these, apply new label of 2200+ or whatever, nd sell at higher prices.
if ur CPU has been showing 2200+ in start, then the problem is with BIOS (check settings, check Battery of Motherboard as well)