just need to understand more b4 i overclock

[dansonang]

how does increasing the fbs affect the agp and pci slots. I have got a 1.8a northy. i wan to increase to fbs from 100 to 125 to 130. since I am increasing the speed to the 2.2 and 2.4 ghz range, should it be a concern for me. i am no serious overclocker. thx. help appreciated

[batboy]

Some motherboards (like the Abit TH7-II) has a setting that allows you to fix the AGP and PCI bus speeds. Most other motherboards only have PCI dividers (AGP is usually double the PCI bus). Some mobos allow you to change the dividers too. Typically, from 100 FSB and above, a 1/3 divider is used. At 133 FSB, a 1/4 divider kicks in.

Running the PCI bus too far out of spec often causes instability and possible harddrive data corruption. Most of the time 112 FSB with a 1/3 divider is pretty safe on the components. I've had fairly good luck using 115 FSB too, but above that gets shakey.

The next step would be 133 FSB since that allows the use of the 1/4 divider and puts the PCI and AGP back into spec again. The 1.8a Northwood generally will handle 133 FSB (2.4 gig) without too much trouble if you have good cooling. You might have to bump up the voltage a notch to be rock stable. Make sure you have good cooling before raising the voltage. Good luck.

[dansonang]

what does the divider do? if i overclock to 2.2 to 2.3 by increasing to 130fbs should I change the divider?

[batboy]

Short answer: yes. The default PCI speed is 33.3 MHz. A system that runs at a default 100 FSB has a 1/3 divider (100/3=33.3). If you try to run 130 FSB using the 1/3 divider, then your PCI bus speed will be at 43.3 MHz, which ain't gonna happen (it'll never be stable). Why not shoot for 133 FSB so you'll have the 1/4 divider and have everything in spec? If you use the 1/4 divider with 130 FSB (some motherboard allow this and others don't), then your PCI and AGP buses will be slightly underclocked. This will hurt performance a tiny bit.

[dansonang]

changin both the dividers and the fbs is done in the bios right?

[micamica1217]

Originally posted by dansonang
changin both the dividers and the fbs is done in the bios right?

yep.:D

remember to look at cpu temps at full lode...keep them under 50c .


mica

[dansonang]

I believe I have got enough room to overclock. at full load my temp is 42 at an ambient of 31. my idle is only 35 to 37