FSB and AGP interaction

[OC-noob-]

When overclocking my puter, what does increasing the FSB do concerning a graphics card in an AGP 8x slot... in my case a gf4 ti4200 in an ECS L7S7a2 mobo.

Does it increase the bandwidth btw the cpu, mobo, and gfx card?

does it make the gfx card run better (i.e. give you better fps)?

[Graphic67]

Welcome to the Forum!

I am not too familiar with the behaviour of SiS chipset boards, but in general before the nForce2 boards became available your AGP and PCI busses operated at a fraction of your cpu bus speed (i.e. 3-2-1, 4-2-1, 5-2-1, 6-2-1 for fsb-agp-pci ratios). With that board you may be running a 4-2-1 divider so for every 4MHz higher fsb, your agp goes up by 2MHz and your pci goes up by 1MHz.

This will increase the bandwidth slightly, but you also run the reisk that the agp or pci cards will not operate with the higher speed. Since your board is an 8x AGP and most games do not fully utilize 4X yet, you will not be likely to notice any change in performance. Some benchmarks may improve, but only a little.

The real improvement from higher fsb is that you increase the bandwidth between the cpu and the northbridge and thereby to all the I/O devices in your system (hard disk controllers, network, etc...).

[aznchaos]

I have the same motherboard and i think that the agp is locked. I dont really now what that means but i think its not affected but im not sure.

[modenaf1]

http://www.theforumisdown.com/uploadfiles/0103/welcometotheforums.JPG
well, if your board locks the PCI/AGP bus, it wont do anything, but it depends on your divider, my board gives me 2 options for my divider

1-2-4 and 1-2-5 or something similar. i cant explain it real well but bassically it divides the fsb and agp.pci so they dont run out of spec and then usually for overclocking your video card you download software. ;)