Reduced Memory Footprint sa WIN7
One of the big goals for changes in DWM is to reduce the memory usage. When 2d applications are drawn to the desktop they are drawn through a system component called GDI, which is the case for both Windows Vista and Windows XP.
Sa Windows XP, When drawing to the desktop the window for the 2D application (such as notepad or Microsoft Word), it first gets drawn to GDI, which would create an image of that window in system memory (RAM). GDI would then draw the window directly to the screen since it was responsible for drawing the desktop.
With Windows Vista a new display model was introduced where the work of compositing the desktop was handled by another system component called the DWM, or Desktop Window Manager. DWM used the 3D hardware of the video card to draw the desktop so that this work could be done by dedicated hardware that was more suited to drawing images, and enabled effects like transparency, video thumbnails, and Flip3D
In Windows Vista GDI is still in place, but instead of GDI writing directly to the screen, it would pass the copy the image of the application window to the DWM which stored that copy in video memory so that it could be drawn to the screen. The problem here is that we are now maintaining two copies of each window image; one in system memory and one in video memory, and this resulted in excessive system memory usage.
Ngyun with Windows 7, the new version of the DWM no longer needs the copy of the window image stored in system memory. The window image is only stored in video memory, freeing the system memory for use by other applications.
WDDM 1.1 drivers will be required in order to realize these benefits. Using WDDM 1.0 drivers will retain the old Windows Vista behavior.kaya dapat no problem if you're currently with vista,sabi nga nila samin eh vista is just an unfinished windows 7
