I wouldn't be too optimistic about getting it massively higher than that tbh, most B3s max out somewhere around 3.2-3.4, you might get a few to 3.6 with a decent VID/lapping/bit of luck.
Get the Obsidian and a H50, and go for about 3.2 on your Q6600, it'll last you a while yet.
You'll have a smexy case, and decent cooling for anything you change to in the future.