Hi, I have been looking forward to purchasing a 4-core cpu to replace my phenom II X2 550 that i've had for like 2 years lately but I decided to try to unlock it and maybe I could save some bucks. My CPU-Z screen is in the attachments. Basically, I have a Gigabyte GA-MA785G-US2H revision 1.1 mobo with F11 bios. My cpu is Phenom II X2 550 Black edition codenamed Callisto. According to wikipedia, Callisto archs have 2 cores locked, so, unlockable maybe!? So, I changed ACC to auto and EC firmware to Hybrid, saved settings and rebooted. Surprisingly, the machine booted fine! However, when I check on CPU-Z, nothing's changed! It's still Phenom II X2 with 2 cores and 2 threads! I checked in msconfig as well and there are only 2 cores! Can't say that the machine is really stable though! It IS stable, but not like when ACC is disabled! Because the machine booted fine, I assume that the dormant cores aren't really faulty right? Or, are they? Is there something more I need to do to have those cores unlocked?