dedicating video memory

i have 512 mb of dedicated video memory out of 3.072 gb. can i dedicate 1gb to my video memory? my system specs are : was windows 8 factory but now running on windows 10 amd a6 5400k dual-core processor amd radeon hd 7540d graphics 1 tb hd 6gb ddr 3 memory make and model- gateway dx4380g-uw308...