Questions on a toshiba l505d and vram?

i was messing around on my old hp and in the bios there is a section to change the amount of vram you use(32 64 and120) or something like that. when i go into the bios on my toshiba i don't see anything about vram. i play games like diablo2 lod and my wife plays sims3, is there anyway to boost the graphics and things to play better? can you change the vram on a toshiba satellite L505D G6000 with win7, 4gig ram, and a amd ati integrated chip set? j/w 0_o