Asus
N56JR-S4018H, i7-4700HQ + Nvidia GTX760M + (1920x1080)@RM3999[2.7kg], 12GB, 1TB, W8.1, backlit keyboard
Lenovo
Y510p, i7-4700MQ + Nvidia GT755M(GDDR5) + (1920x1080)@RM3399[2.7kg], 8GB, 1TB, W8.1, red backlit, swappable ODD, 120w psu, 2 yrs
Y510p, i7-4700MQ + Nvidia GT750M(GDDR5) + (1920x1080)@RM3999[2.7kg], 8GB, 1TB, W8, red backlit, GN37 exGPU & ODD, 120w+170w psu, 2 yrs
Only the single GPU Y510P is within your budget
Anyway, GT755M vs GT760M is pretty close performance wise. As for GT750M SLI, for games that support SLI, it's close to GTX770M level (with caveat such as drivers support, micro-stuttering, etc).
Since you've narrowed down to 2 models, I suggest you go out and look / type / click / listen / type / carry the real things to see which you prefer

thx bro for your information ... i might getting the N56JR .. in my area , they doesn't have the demo unit for me to try .. so i can only get information from lowyat.net .. is it heavy for the N56JR ? cause i might carrying in and out to campus ..