AGP Driving Value explained

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In your BIOS, you may have an option called "AGP Driving Control" that you can set to Auto or Manual. Selecting the Manual option will allow you to specify AGP Driving Values (in hex) from 00h-FFh. The presence of the AGP Driving Control is specific to VIA chipsets, so if you have it, you have a VIA chipset (more on that later).

The AGP Driving Control allows you to control, quite specifically, the AGP driver signal strength. Due to the design of the AGP protocol (which specifies the bus as well) this is directly related to timing. So, by selecting a manual hex range (00h-FFh) we are setting the timing of the signal that your video card's driver uses to communicate across the AGP bus.
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