Each stage in the graphics pipeline adds overhead to the rendering. Stages can be removed from processing by clicking on the GFX Core component and then disabling stages in the Configuration Options panel belonging to the GFX Core:

For example, the Alpha Blending stage can be disabled if your graphics application does not use alpha blending. If the color mode of the display matches the color mode of all images you can disable Color Conversion. Disabling unneeded stages can improve performance and reduce code size. 

Also, a graphics controller driver may add additional stages, or opt to bypass stages completely depending on the capabilities of the graphics hardware supported by the driver.