Heatpipes have been the recent trend among heatsinks and Thermalright is no exception. The popular SP-94 and SP-97 both use heatpipe technology and have been top performers in their respective classes for a while now. Thermalright seems to have hit a size/weight limit with their copper heatsinks and have introduced a few aluminum products. They started with the ALX-800, which is like an aluminum version of the SLK-800. Then they released their first northbridge heatsink fan, the NB-1, which was also aluminum. Their latest releases, the XP-120 and XP-90, use heatpipe technology and the advantages of aluminum to differentiate themselves from the rest of the crowd.