The processor was originally designed to link to fully buffered DIMMs. But Intel has dropped plans to use FB-DIMMs for its Xeon and Itanium servers CPUs, opting instead to use DDR3 and with new external memory buffer chips designed by Intel.

"That entire memory buffer chip didn't exist a year ago and now it's a core part of the architecture," said Kirk Skaugen, general manager of Intel's data center group.

 

The switch to DDR3 caused a year delay in releasing Tukwilla, he added. The last time Intel released an Itanium chip was in 2007.

With Tukwilla, Itanium and x86-based Xeon processors from Intel now use in common the QPI processor interconnect as well as I/O and memory buffer chips. HP would not say if it will design a single node controller spanning high-end Xeon and Itanium systems or whether it will continue to make its own Itanium I/O chips.

 

The Tukwilla processor includes four dual-threaded Itanium cores, up to 24 Mbytes cache and a memory controller. It runs at data rates up to 1.73 GHz and sells for $946 to $3,838 depending on configuration and quantity.