Which video card is better: GT 740M_1Gb or GT 710M_2Gb?

Question

Iron

and how much better? is it significant?

Answer 1

Table of mobile video cards
In general, 710(M) is a low level (weakest) card from the entire family. 740(m) middle-low seems to be.

Answer 2

Look at the characteristics and choose, who knows what is your criterion for the best?
GeForce 710M - 96 cores 800MHz - 12W
GeForce GT 740M - 384 cores 800-1000MHz - 45W
en.wikipedia.org/wiki/List_of_Nvidia_graphics_proc...