Talking about power consumption, we should also mention the fact that Intel’s engineers have improved the hardware monitoring system that controls the speed of the notebook’s fans. Core Duo processors are equipped with two integrated digital temperature sensors placed in the hottest spot of each execution core. Precise control over the CPU thermal conditions is thus possible and this should ultimately lead to quieter cooling systems (if the notebook manufacturers take the right approach to developing them, of course). There is also a third, common sensor in the Core Duo which is left for compatibility with older hardware monitoring systems.
This is where the architectural difference between the Core Duo and the Dothan-core Pentium M ends. We should only add that the new mobile processor supports Intel Virtualization Technology , but it is unlikely to be used in mobile computers. It must have been implemented in the Core Duo because Intel is going to promote this processor as a possible foundation for the entertainment platform Viiv.
You may have noticed that we’ve never mentioned Enhanced Memory 64 Technology (EM64T – 64-bit extensions to the x86 architecture) in this article so far. Unfortunately, the new Core Duo, like its predecessor Pentium M, is a 32-bit processor. Well, you should realize that the Pentium III, the forefather of all modern notebook-oriented CPUs from Intel, came to market back in 1999 and had nothing to do with 64-bit software applications. It would have taken a thorough overhaul of the micro-architecture to implement x86-64 support in the Core Duo, and Intel wasn’t ready for that. But Intel is already working on a next generation of mobile processors currently known under the codename of Merom. This true 64-bit CPU is expected to arrive to market in October-November this year and will make a cause for an update of the Centrino Duo platform.
Physically the Intel Core Duo chip has a 479-pin packaging, but is not compatible with Socket 479 mainboards. We aren’t surprised at that at all as Intel has made a point of changing its CPU sockets regularly.
The new processor’s pin values are different from those of the Pentium M. The pins of the Core Duo are also placed in a different way. This raises a physical barrier against upgrading an old mobile computer with the new dual-core processor. Moreover, the new CPU uses a faster Quad Pumped Bus (667MHz instead of 533MHz), which is quite reasonable considering the doubled number of execution cores. Unfortunately, this is still much below the peak theoretical bandwidth of dual-channel DDR2-667 SDRAM employed in modern notebooks – 10.7GB/s.
Like the modern dual-core processors fro desktop computers, Core Duo processors are manufactured on the new 65nm P1264 tech process. Intel has managed to transition to the more advanced manufacturing technology sooner than the competitor; AMD is only going to transition to 65nm at the end of this year at best. Thanks to the new tech process, the 151.6 million transistors of the Core Duo processor occupy an area of only 90.3 sq. mm. The dual-core chip is a mere 8% larger than a Pentium M on a single 90nm Dothan core, which means its production cost isn’t going to be high (if the tech process runs smoothly).