So the title says it all .. I have come to two different Lenovo z500 models. One with GT645M dedicated graphics and one with GT740M (as far as I know it is only 64bit version with GDDR3) I have question which option is better. Acording to some benchmarks run by one friend on his Lenovo E531 with i7 processor and GT740M(gk208) the results for this graphics card are just 20% above the GT635M. Any one can confirm ?