My computer doesn't recognize all of my ram can i fix this?

Your computer likely is using part of the RAM for what is called "Shared Video Ram". Your average bottom-of-the-barrel bargain machines use shared ram to keep from having to spend money on dedicated memory for video chipsets. If you hit the "Enter Setup" option when your computer is turning on, there should be an option someplace for shared graphics. It will let you turn down your RAM usage for it to get more for other things.