XFX R7770 Black Edition S Review @ Vortez
 

Enter the XFX Black Edition. With an improved over-stock clockspeed of 1120MHz on the core (120MHz faster than reference HD7770) and a huge boost on the memory clockspeed to 1300MHz (5200MHz effective), the Black Edition 'S' (Super Overclock) arrives pre-overclocked which should give the card a fair boost in performance.

http://www.vortez.net/review.php?id=498