Windows Display Driver Model in Windows 7



Windows Display Driver Model is also known as WDDM. It is the new engine that Windows 7 uses to display virtually everything you see. It is built to be stable and fast, and to make much better use of your computer’s resources than any previous version of Windows ever did.

In older versions of Windows, a powerful graphics card and its local memory often went unused except when the user played a game. WDDM uses the graphics processing unit (GPU), which is the main chip on your computer’s graphics device, and its memory as part of its display architecture.

That is why the new operating system has such severe graphics card requirements. Gamers who put a lot of money and faith into their computers’ graphics hardware should love the fact that not only their games but Windows itself is making the most of it.

Windows realizes this efficient resource usage with two major components: a GPU memory manager and a GPU scheduler. The memory manager decides where in video memory Windows data are to be stored; the scheduler decides in what order data need to be processed to make the most efficient use of the computer’s hardware and to offer the user the smoothest experience.

The WDDM also results in a vast improvement in computer stability. Display drivers—the drivers that arbitrate between Windows and the graphics hardware—are vast, unwieldy, and extremely important components of any computer system. Traditional display drivers operate at the kernel level, and one minor bug or glitch can cause the entire computer to hang, or even to cough up the dreaded blue screen of death.

WDDM drivers have two levels: a smaller, more streamlined, and more stable kernel mode driver, and the larger user mode driver, which gets care of most of the major calculations. Because most of the driver activity takes place outside the kernel, malfunctions are far less prone to result in catastrophic failures. In fact, the vast majority of driver problems should affect a single application or game, and not the entire computer.

WDDM also permits for all kinds of cool effects, like the Aero glass effects, Flip 3D, live icons and taskbar buttons, and more. It adds to the stability, usability, and appeal of the graphical user interface (GUI).