In essence the new Xeon isnít that different from the Pentium 4, much like its predecessor the Pentium III Xeon wasnít that much different from the Pentium III. If we take a closer look at the differences between the Pentium III Xeon and the Pentium III one things is obvious, the Xeon is available in a number of different L2-cache configurations that cannot be had with the Pentium III and only comes in a Slot-2 form factor. Other features include the variety of advanced management features to monitor and safeguard the CPU to ensure it runs safely and within operating conditions. Naturally these advanced features cannot be found on a regular Pentium III.
With the Xeon DP and the Pentium 4 itís a different story all together, both use a socket approach, but the Pentium Xeon DP uses Socket-603 and the Pentium 4 Socket-423. Although that makes perfectly clear that the Pentium 4 wasnít meant to be pin-compatible, it also indicates that the Pentium 4 core needed a lot more pins to enable SMP, dual processing, and include a number of advanced management features as weíve seen on the Pentium III Xeon.
One other thing thatís worth mentioning is that the Pentium III Xeon was never really targeted towards the high-end workstation, it simply was restricted to the server market due to the supporting chipsets and motherboards. These never really offered the cutting edge performance needed to enable high-end workstation class performance. However with the Pentium Xeon DP Intel takes a whole different approach, the Xeon DP is designed to go head to head with the likes of Sun and SGI and other high-end workstation manufacturers, and server versions of the new Xeon MP are to be introduced later this year.
Fig 2. Intel Xeon DP CPU, notice the very small form factor of the socket-603 and the large number of pins concentrated in a small area.