On September 15th Intel plans to fabricate the Intel Xeon 7400 Dunnington series processor, the company's last Penryn generation processor to be released. Xeon 7400 will mark the end of a previous server era, and after it the new Nehalem Core i7 processor family will start to appear in the fourth quarter. The Xeon 7400 will be Intel's first 6-core server chip. It will be produced using 45nm high-k process technology and will boast 16MB of L3 cache. The Xeon 7400 Dunnington series is also one of the first Intel chips to have a monolithic design, like Nehalem. In other words, all six cores will be on one piece of silicon.
Source: Techpowerup