Which is better between 3rd generation i3 and 2nd generation i5

i5 will be better for gaming despite being a last gen part.

2GB graphics card? Which one?

@amuffin

Kind of hard reading their posts....considering the way they type. Well, English probably isn't their first language...

Nah, fair enough dude.

Generally speaking the Sandy Bridge Core i5 will give you better performance than the Ivy Bridge Core i3 CPU. Ivy Bridge CPUs are on average 6% more powerful than Sandy Bridge CPUs; assuming the same clockspeed. Since this is a laptop both Core i3 and i5 are dual core CPUs.

However, Core i3 CPUs lacks Turbo Boost which is an automatic overclock. The actual Turbo Boost clockspeed depends on the CPU's temperature and how many cores are used. For example, my Core i5-2410m has a normal clockspeed of 2.3GHz; as long as the CPU temp is not too high it can reach a max clockspeed of 2.9GHz if only core is used and 2.7GHz if both cores are being used.