Iphone

Just like in a 3D game title the graphics card can improve the speed at which your computer operates by off loading the very intense computational workload that is required to generate 3D effects from the CPU (central processing unit) to the GPU (graphics processing unit) of the graphics card. This offloading of work to the GPU from the CPU frees the CPU up from generating the interface and allows it to focus on running the other system tasks making the entire computer system more responsive.
With all of this said, the most basic point of using a graphics card with Vista isn’t that it makes things look more attractive, which it does. The point here that people need to realize is that using even a $50 graphics card in a Vista equipped computer can improve the performance of the entire system by freeing the CPU up for other tasks. Vista is the first operating system where a dedicated graphics card can affect system performance overall. What we will now see is that rather than only gaining performance improvements from upgrading components like your RAM and CPU to make your system faster and increase your productivity you now have the option of adding or upgrading your graphics card as well, and a graphics card can be upgraded for much less money than your RAM or CPU.



source:Windows Vista Aero Needs a Graphics Card