It is possible to speed up the PC video subsystem, not only by increasing the clock frequencies of the AGP bus, video chip, and video memory, but also by modifying the hardware of your video adapter.
(Based on materials and with the permission of http://www.fcenter.ru, a Russian-language Web site.)
The performance of the video subsystem, represented by the video adapter, strongly depends on clock frequencies. Clock frequencies determine the operating modes of the graphical video core and the video memory.
The range of clock frequencies that can be set independently for the video core and video memory can be widened significantly by increasing the supply voltage.