Basic Question on GPU

[humble_learner]

Hi,

Other than the fact that a GPU can perform heavy calculations for rendering and shading, what are some of the other salient differences between CPUs and GPUs.
Can the CPU not be used for rendering graphics on the monitor - is it always the GPU that is required to do this ?

Basically, can there be a basic computer system (not running high end graphics but running basic Windows applications) without a GPU being present on the motherboard ?

[olivthill2]

An important task is to refresh the screen by sending data from the video memory to the monitor. There are special timings to refresh a line or an entire screen. Video (or graphics) memory is not always the same than ordinary RAM.

Some Windows computers don't have graphic cards. They use "integrated solutions". See http://en.wikipedia.org/wiki/Graphics_processing_unit

[Mike Harnad]

Think of it as a division of labor. If the CPU can pass of responsibility for managing the screen to a GPU, it can then spend more time "processing". In theory, this should lead to better throughput for applications. the contrary is also true. If the CPU has to manage the screen, it has less time to "process".