I have a GA-Z77X-D3H motherboard with 16GB RAM and a i3-3220 CPU which I know is kind of bottom of the barrel as far as CPU's go. I want to upgrade to a better one, but I can't seem to find a compatibility chart anywhere even on Gigabyte's website. I know that upgrades depend on BIOS type (so I've heard. like FA, FB or whatever) how can I tell what BIOS I have and what CPU's are compatible with my MB? I am retired and surviving on Social Security so I can't afford a lot. Also I have seen some used CPU's on Ebay and wondrered if they would be reliable? Any recommedations or help would be greatly appreciated.