How to increase graphical performance?

Hello users,
My PC's graphical memory is low I think. Graphical memory is 762 MB. How can I increase this limit? I specially recommend to give me tips on how to use USB Flash Drive as graphical memory. Any other way is also accepted.
RAM is 2 GB. Processor is Intel Core i3 (3.06 GHz). Motherboard is Intel DH55PJ.
Please give me any solution.
