Windows utility to alter FSB of Core (2) Duo Motherboards?

Is there a Windows program that can alter the FSB of a Core Duo or Core 2 Duo motherboard? I seem to recall that Aopen provide a utility that allows this with their 975X based Core Duo board, so I’m wondering if there’s a generic solution that supports Intel chipsets.

I’m aware that Clockgen can do this, but only for a limited number of compatible boards. I’m wondering what other utilities are available that also do this.

Since I want to under-clock as well as over-clock the FSB I'm wondering what the lower limit will be. 800 shouldn't be a problem for desktop boards as some chips use that anyway; is 667 going to be possible with the desktop chipsets (965)?

I can understand wanting to undervolt and/or drop the multi but the FSB???

the PPL isnt compatable with some of the new Core2 mobo's with clockgen, SoftFSB has been contacted with a request for an update I dont know about clockgen

The Bios is always an option

btw.. these should be compatable with smithfeilds and some of them are 566FSB stock.

greenmaji said:

I can understand wanting to undervolt and/or drop the multi but the FSB???
The Bios is always an option
btw.. these should be compatable with smithfeilds and some of them are 566FSB stock.

Click to expand...

I checked the P965 chipsets and it supports 533 MHz, so dropping the FSB should be no problem.
The reason for wanting to drop the FSB is this:
Core 2 Duo uses a minimum multiplier of 6; this means that Speedstep is restricted by this and can’t go lower. If I over-clock an E6600 to 1333 FSB, its minimum speedstep setting becomes 2GHz which is too high for me. For general computing needs I don’t need a Conroe @ 3 GHz, so I can set the FSB at 533 or 667, undervolt the CPU and get a nice low power setup. When I need the extra performance, I run a different copy of CrystalCPUID with the voltages optimized for over-clocking, then up the FSB to 1333 or higher. Doing this in software is much quicker than entering the BIOS.
This is a bit like having an X6800 and a U2500 in one chip. With the FSB at 533 the E6600 runs at 1.2 GHz like the U2500; push the FSB up to 1333 and the E6600 is hitting 3 GHz which puts it in X6800 territory.

Less CPU power

Ok.. saving some power is OK

I was thinking undervolting only