Build looks good. Id recommend the GTX 560Ti over the 6950 though.
Also 650w PSU isnt quite enough for an SLI set up and is over-kill for a single card. Id either look towards a 750w PSU or just buy a 500w unit. Recommended brands include: Corsair, Antec, SeaSonic, XFX. Look for 80PLUS ratings
PSU that available in my area. Which is better?
THERMALTAKE TR2 Bronze 500W *80 Plus Bronze
AEROCOOL STRIKE-X Series PSU 500W *80 Plus Bronze
CORSAIR Builder Series™ CX500 *80 Plus Bronze
SILVERSTONE ST50F-ES (500W) *80 Plus