The only reason I got rid of my northbridge cooler is because it was too loud. I replaced it with a passive heatsink, and its still good up to 228mhz. Seriously, the northbridge does not need much cooling at all. I'd also heavily advise against a Tornado. I once used to a have an equally loud Delta 38, and I couldn't take it. No overclock is worth that excruciating noise level. Just buy a Smartfan II, and in that case, save some money and go with an SLK800. At that point, further cooling won't accomplish anything.