why the heck would you get a 3820 in the first place? the 3770k performs better and if you want more power, the 3930k is even better. if you are upgrading your build when ivy bridge -e comes along, it would mean a waste to the 3820 since its still very fast
overclocking is just free performance. not much, but still a good amount.
overclocking on a 3820 is slightly different since you use the bclk from what i know
you dont need that much ram unless you are building a ramdisk or doing extreme rendering