You will probably have to play with less textures and a worse framerate. Halo was originally designed for XBox which has 64MB of memory. You really need more memory for optimal preformance. I recommend AT LEAST 64 MB for Halo and many other current 3D games. You said you already got the notebook right? If you havent and have the money, I suggest getting the new Alienware notebooks as you can actually update the graphics on them, something new to notebooks.