Well Video Ram on your GPU would have an effect if your running a high resolution monitor like 2560x1440 resolution or if you are doing anything production based like rendering a higher video ram will have an effect.
If all you are doing is gaming, the difference between 1 and 2gb of ram shouldnt make a massive difference if your running a standard HD monitor and you're not obsessed with playing every game at max settings.
If you want more background information on video ram there is an article here on toms actually. its a bit older but the information on the video ram is still good.l
http://www.tomshardware.com/reviews/graphics-ram-4870,2428.html
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