Wednesday Intel took the wraps off the next iteration of its Xeon server line, the Nehalem EX, which will debut in the second half of this year. Nehalem EX has up to 8 cores, which gives a total of 16 threads per socket (with hyperthreading). That's a lot of threads in one socket, so it's good that Intel outfitted the chip with plenty of I/O and memory bandwidth in the form of four QPI links and two integrated memory controllers. Also helping to keep the cores fed is a 24MB cache.

The whole thing weighs in at 2.3 billion transistors, which is even larger than the record-breaking 2 billion-transistor "Tukwila" Itanium that Intel unveiled in February of last year. At the time, the quad-core Tukwila was Intel's largest processor, and the fact that an x86 part has caught up with it in size and will launch ahead of it (Tukwila is delayed yet again) says something about where Xeon is headed.

Nehalem EX will pack quite a performance wallop when it drops later this year, continuing x86's decades-long march into the very high end of the server market. I interpret recent remarks by IBM that x86 virtualization isn't ready for use in real mission-critical applications in light of this reality. Not that Nehalem-EX-based systems are an immediate threat to IBM's POWER line, but since the company sells systems based on both chips it will continue to take pains to stress the advantages of its own high-end hardware in the face of feature and performance increases from Intel. Drawing this distinction was particularly important this time around, since IBM participated in the Nehalem-EX reveal to tout a 64-core, 128-thread server of its own based on the new processor.

Here's the full Nehalem-EX feature bullet list:

Intel Nehalem Architecture built on Intel's unique 45nm high-k metal gate technology process

Up to 8 cores per processor

Up to 16 threads per processor with Intel� Hyper-threading

Scalability up to eight sockets via Quick Path Interconnects and greater with third-party node controllers

QuickPath Architecture with four high-bandwidth links

24MB of shared cache

Integrated memory controllers

Intel Turbo Boost Technology

Intel scalable memory buffer and scalable memory interconnects

Up to 9x the memory bandwidth of previous generation

Support for up to 16 memory slots per processor socket

Advanced RAS capabilities including MCA Recovery

2.3 billion transistors

On the AMD side of the fence, the six-core Istanbul will launch next week and will take on Intel's six-core Dunnington Xeon. Because Dunnington is a drop-in replacement for Intel's legacy, pre-QPI Xeon parts—it was introduced as a sort of stop-gap for the Xeon line while we waited for Nehalem to go multisocket—it'll be a much easier target for Istanbul than QPI-enabled, bandwidth-heavy Nehalem-EX. The latter chip will be well out of reach of Istanbul in terms of performance.