Definately go with an all copper heatsink. I bought one from TigerDirect... it's the one with the "Medium" speed fan that's 5500 RPM... and there's the high speed fan that's 6500. With the copper heatsink, some Arctic Silver 3, and the 5500 RPM fan, the XP2000 with Palomino core would run at 107 degrees F under 100% load for 12 hours... (did a torture test with Prime 95)