I've got a problem with my graphics card. In Windows XP my graphics card is shown as size: 256MB, but in Windows 7 it is shown as size: 64MB, and I can't run some games. I want an explanation. Thank you.
I guess you're talking about the video memory size. Intel GPUs dynamically allocate RAM as video memory, so the amount used can change. It's a good thing if Windows 7 is using less memory when GPU load is low. This is by design and problems with running some games is probably unrelated.
You can ask separate question about the games problems, then we'll try to solve them.