As most of us already know many of AMD's new dual and triple core Phenom II chips are actually quad core chips with the third and/or fourth cores disabled do to various issues. We also know that when coupled with the proper motherboard these relatively cheap CPUs can be unlocked turning them into a higher end quad core chip.
For obviously reasons this discovery was troubling news for AMD who is now planning to release a new microcode for motherboard BIOS updates that will disable the core-unlocking feature, blocking people from unlocking the disabled cores.
So what can you do? Well the obvious would be to not update your motherboards BIOS. But sometimes that isn't an option. Motherboards makers do from time to time add very important feature updates or fixes that you'll need. The other option would be to buy yourself a dual bios Gigabyte board.
According to Tom's Hardware Gigabyte said that their dual BIOS boards will store the old microcode in the secondary BIOS chip, and allow you to do normal BIOS updates on the primary chip. When you update your BIOS, your system will boot using the new BIOS code but it will be injected with the old AMD microcode, allowing you to continue to unlock your CPU cores.
Of course this hasn't been confirmed, at least not yet. So it might be a bit of a gamble, then again it's a bit of gamble anyways as you might not have a Phenom II that when unlocked will be entirely stable. So proceed with caution.