According to your post in the
this thread, he is using the stock heatsink and fan. I suggest that he gets a better setup than that. Something like a Vantec Aeroflow or a Thermalright SK-7, SLK-800 or SLK-900 with a decent 80 or 92mm fan.
As I mentioned in the other thread, I was able to overclock my 2500+ Barton from 1.83Ghz to 2.3Ghz (almost 500Mhz), and I was using an SK-7 and a Vantec Tornado. The Tornado wound up being to loud for me, so I go rid of it and I'm now using a 92mm Sunon that puts out ~50cfm and is much quieter. I think the fastest I've had my cpu with that fan is ~2.1Ghz.