ProDAD - Support :: ID [46 ] :: 2007-01-03

Answer:

General information:
On some systems, the CPU (Central Processing Unit), located on the motherboard, is responsible for general graphic/video processing. If no graphics card is installed, all the rendering of graphics or video, must be done by the CPU.
On a system with a modern graphics board installed, the GPU (Graphic Processing Unit) assumes the processing load for much of the specialized graphic operations. A GPU is located on the graphic card and acts as a co-processor, along with the CPU.As a general rule, the speed and effectiveness of a GPU is usually dependent on its age. Modern graphic boards that include newer GPU's, normally perform many times faster than older graphic boards. 
To evaluate the processor load "Process Explorer v10.21" has been used.
In the examples below, we used VitaScene (preset #47) to compare performance


Image #1
The Green Line represents the total CPU usage. The red line represents the necessary "kernel" processing requirements. The difference between the green line and the red is the actual demands that the application, in this case VitaScene, is making on the CPU
This a modern system with an installed graphics board. Notice the very low CPU/GPU processor load. Because modern GPU's are much more effcient in their specialized processing, this allows the CPU to be much more efficient. As a result, the overall speed and efficiency of the system is enhanced dramatically.

Image #2
This is an older system with an older graphics card. Because there is no GPU to take up the load, the "kernel" processing, as well as the application processing are pushing the CPU up to 50 percent of capactiy.

This means:VitaScene can be used on older graphic boards which are compatible with DirectX 9c (just check with the Check-program in the bottom link). But with older technology, a performance loss must be expected.But even this loss in performance, from an older graphics card, will never be as high as loss in performance that comes from using CPU-rendering only.Remedy in terms of maximum speed and performance:Use an up-to-date graphic board. We suggest that ideally, a PCI-Express board will provide the best performance.