How do I Test the RAM in Video Graphics Card in Windows XP?

I have brought a New Computer which has an ATI Video Graphics Card, the supplier has said it is 512 MB, but I need to confirm it, how can I do that?

If you want to Check the RAM installed in your PC, you go to MyComputer/Properties/General Tab it shows what is the processor speed,RAM installed etc, is there anyway we can check for the Video Graphics Card.|||Sart-> Run-> Dxdiag-> (display tab) It should tell you your video memory.. Or you can google that perticular video card and see what poeple says about it|||yeah other person is correct or choose display in control pannel settings then adapter this normally gives the memory on the graphics card.