Oh yes thats ture !!
U can unlock the 2 dormant cores on an AMD 7750X2(Kuma) as seen here:
techPowerUp! News :: Athlon X2 7750 BE Unlocked to Quad-Core

For those who have this and a 790GX mobo, can try it and see if they get lucky, plz report bak if u do get it 2 work !