Source written by Keith O'Conor find his blog and further reading at the bottom of this post. All credit goes to Keith O'Conor.
GPU Performance for Game Artists
Performance is everybody's responsibility, no matter what your role. For artists, a little knowledge of what goes on under the hood can make a big impact on a game's framerate. If you're an artist and want to understand how the GPU works and why things like draw calls, LODs, and mipmaps are important for performance, read on!
www.fragmentbuffer.com