Intel has begun sampling the first ever processor with more than one billion transistors on a single die, representing an important benchmark in chip technology.
The next-generation "Montecito" Itanium 2 processor has been supplied for a few select customers, the chip giant confirmed. It is one of Intel's first dual-core products, which put two duplicate processor cores on a single die to boost performance while allowing the cores to run at a lower frequency. The dual-core Itaniums, along with dual-core Xeons for mid-range servers, are expected to launch in full production volumes early next year.
Intel has been talking about breaking the one billion transistor mark since 2002, when it demonstrated the 500 million transistor "Madison" version of the Itanium 2. "It's not rocket science and we are well on our way," said Intel president and chief operating officer Paul Otellini at the September 2002 Intel Developer Forum.
Besides Itanium 2's already high transistor count, a big boost comes from the switch to dual-core, a technology used in server chips from the likes of IBM and Sun for years. In addition, the chip is expected to integrate 26.5MB of cache memory, adding more transistors.
Each core has its own memory cache, Intel has said. It is technically possible for the cores to share a cache, but this can mean a daunting engineering challenge.
To fit it all in, the chip will have a massive die of about 580mm squared, according to reports. For comparison, the second-generation Itanium produced in 2002 was about 400 to 450 square millimeters in size, and that was about the biggest chip that had been produced at the time.
Since then, Intel has moved from an 180nm (nanometre) manufacturing process to a 90nm process. That reduces the geometry of the chip's features, allowing more transistors to be squeezed into any given space, and allowing the chip to run more efficiently and to produce less heat.
IBM's Power5 chip is considered complex, but it has fewer than 300 million transistors.
Intel has steeply increased the number of transistors in its chips over the past 20 years. The 386 chip of 1985 had only 275,000 transistors, and the 1 million transistor mark wasn't broken until 1989 with the 486 chip.
The Pentium broke three million transistors in 1993, and its successor, the Pentium 4, reached a new level of complexity in 2001 with more than 42 million. The original Itanium 2 in 2002 had more than 220 million transistors.