Overclocking question about memory

[excalibur2]

I'm overclocking this older board and it's using Corsair PC3200 with a core duo E2140 and I'm confused with some settings in the award bios:-

So far I have reached 2.2ghz which you can see the bios settings below i.e. 8X275 but what I'm not sure is what to set "memory frequency For" ......I have a choice of 1.33, 1.66, 2, auto....and it's link to "cpu host frequency" i.e. 275X1.66=457

Cpu clock ratio------------------ 8X
Cpu host clock control----------Enabled
Cpu host frequency-------------275
AGP/PCI fixed--------------------66/33
Memory Frequency For----------[1.66]
Memory Frequency (Mhz)-------457
Agp/PCI frequency (mhz)--------66/33

Anybody remember the best setting for overclocking.....yeah I know I can use trial and error but would like to start from some logical position.
This gigabyte board ga-81865gme is good value for £30 but the overclocking bit is limited in that so far I can't find a way of increasing any voltages, anyway it might be just as well as the PC3200 is probably stopping a very good overclock.

[schmunk]

At 457MHz, you RAM is likely to be the limiting factor.

I would set the RAM at the lowest multiplier (i.e. from your choices named, I'd use 1.33x for a frequency of 366MHz). This is currently underclocking your RAM, but you can then test the limits of the CPU/Mobo before then bringing the RAM back to whatever speed you want to use.

[excalibur2]

At 457MHz, you RAM is likely to be the limiting factor.

I would set the RAM at the lowest multiplier (i.e. from your choices named, I'd use 1.33x for a frequency of 366MHz). This is currently underclocking your RAM, but you can then test the limits of the CPU/Mobo before then bringing the RAM back to whatever speed you want to use.

Thanks will try...............I'm trying to remember how everything is linked i.e. ram speed, cpu speed, sidebus, timings, frequency etc................and the problem is I only upgrade about every 2-3 years and that is when I do the overclocking and forget in between.