Based on the reviews on newegg, the AMD Phenom II X2 550 Callisto seems to have moderate to great success in unlocking cores. But not everyone is successful.
Can anyone speak to the degree of success, or hypothesize the probability of, associated with unlocking additional cores? I want a quad-core, and may spend the $50 or so extra to guarantee it, but I'm curious nonetheless.
More about :dual core phenom successful core unlocking
If you need a quad buy one but I looked into this alot before I unlocked my 550 BE any anyone that had real numbers looked like 70-90% success rate on the dual and around 50-60% on 3 core chips. Remember the 550BE is C2 but the 555BE & 550 (not BE) are C3.