For starters, I would simply set your RAM for a FSB of 400 and 1:1 memory. That will get you close to 3.2Ghz.
Look at your Temps/Volts and go from there.
3.2 would still be a light OC.
It comes down to if the extra Mhz actually gets you muc.
I know I everntually clocked my C2D back just a tad from my highest OC (Which likely was not even as high as I could take it) just so my fan ran more quiet and never noticed a performance difference.