Understanding clock speed

[Shane72]

Hi,

Unfortunately, when I first began building computers, the motherboard manuals came with a chart where you simply chose the mhz of your chip and it showed you how to set the jumpers. I'm now building new systems, and want to understand how to properly set clock speed and ratio.

Right now I'm building an AMD 1.4ghz with a Gigabyte GA-7VTX board. There is a chart for CPU clock speed where it lists the CPU, AGP, and PCI settings. CPU options are:

- 133.3
- 100
- 166.6
- 110
- 120
- 140
- 150
- 170

How does this relate to my 1.4 ghz processor?

Then, for the ratio, it has 5x, all the way up to 12.5x in values of 0.5 increasing. Can someone please help me to understand this?

Thanks!!

Shane

[wedor]

I would think on that board the setting is 10.5*133=1400.

[kraken]

Sounds right Wedor

133X2(DDR) * 10.5 = 1400

Increasing beyond the 133 by increments can often lead to increases (by increments) of the PCI and AGP settings unless the BIOS fixes it to the static rate.

This can cause some add in cards to work ineffectively.

This only happens when overclocking (sometimes) and if you set the processor speed to the correct FSB then you should have no problems.

[mike breck]

Also a lot of the new Mobos detect your CPU and set the multiplier and voltage automatically in Jumperfree mode. You just need to check the bios and make sure it got it right.

My Asus A7A266 DDR detected everything correctly on first boot apart from the CPU which it listed as 900 instead of 1200. I just changed it to 1200 in the bios and everything was fine. If you want to tinker with switches (for overclocking), then you change it to manual mode via a jumper on the mobo.