Intel Core 2 Duo overclocking

I'm running two instances of mprime torture test on an E6700 2.66 GHz Core Duo @ 3.2 GHz, and I can't get it to fail :) Intel must rank these chips way below potential... I'm using a nice big Zalman heatsink+fan but still. However, I would like to get a southbridge cooler as that chip is getting pretty hot.

I just built a new system.. E6700, 4 GB ram, all SATA, Ubuntu64... I love it :) I'll take some pics soon. Normally I don't name my pcs, but with the black brushed metal CoolerMaster Mystique toping it off I had to go with "Blackhawk" :)