At those settings how would a 7750 cope?
I mean a 7770 will fall well under 30 fps at full settings at 1920 x 1080 so you will need to turn down the settings quite a bit and then video ram does not help.
If you start to push over that screen resolution then yes.
System ram is another beast all together.
Since i do not know of any reviews of the 2gb gddr5 7750's here is something with a bit more power.http://www.techpowerup.com/reviews/Club_3D/HD_7850_RoyalQueen/1.html
I am not trying be an ass or anything, I just do not think mid level cards with lots of vram are at all worth the cost.