The Intel K code update micro-processors block the multiplier and the processor in everything that is not a chipset Z87.
K processors allow, through at a somewhat higher price, use a wider range of internal multipliers which considerably facilitate the potential for overclocking of the processor. Intel aims for these processors to run only in the hands of enthusiasts who are also willing to pay more to use the more expensive and powerful chipsets.
A few weeks ago some manufacturers have begun promising an un-blockers on their motherboards with especially the B85 and H87-based economic chipsets. In this way it is significantly cheaper to leverage the more powerful processor brands. Looks like this Intel was not liked and is forcing its different partners to do bio updates so that through these bio updates these plates are back with the inability to take full advantage of these models of processors.
Updates appear to have been authorized this week so on the next updates of your plate, the code will be present and with the plates that begin to reach the market it could be that they now have this series lock.
