Is it possible to upgrade?

I have a mid 2010 27 inch mac.
I have upgraded my processor from an i3 3.2ghz to a i7 2.93ghz.
My graphics card is an ATI Radeon HD 5670 512 MB
Is it possible to upgrade my graphics card that's more than a 1024mb?
all help would be greatly appreciated!

via ehMac.ca http://ift.tt/21jvZdi