yeah i would suggest underclocking the ram in the beginning, it keeps the ram from being a stability factor while trying to increase your HTT.
also, make sure you lower the HT multi, it will be auto or 5 in your bios, and you want to make it 4 (once you get your HTT to 250 you will want to lower it to 3...keep the HT bus under 1000 for stability reasons).