Chipset

Previous Centrino Duo platform modifications were based on the mobile Intel 945 core logic set. The current platform refresh inspired Intel to replace the chipset with a newer solution – the mobile Intel 965 (also known as Crestline). This chipset can be regarded as a mobile analogue of the desktop Intel 965 with limited functionality.

The differences between the mobile Intel 965 and the predecessor are not dramatic.  The North Bridge has acquired 800MHz bus support, while the rest is the same: it works with dual-channel DDR2-533/667 SDRAM and supports PCI Express bus that can also serve for external graphics cards.

By the way, Intel claims that the mobile Intel 965 will also be able to work with Penryn processors for notebooks, which means that the new chipset has hidden support for 1067MHz bus that is not publicly revealed until the time is right.

Some things have been improved in the South Bridge also. Notebooks using Santa Rosa platform will support three Serial ATA-300 ports and ten USB 2.0 ports in the chipset.

As always, when we get to talk about Centrino Duo, Intel offers two chipset options: discrete PM965 and integrated GM965. Although mobile platform users mostly prefer external graphics solution to Intel’s integrated graphics, Intel provided its GM965 with a new X3100 integrated graphics core with a number of significant improvements.

In fact, X3100 became the first Intel graphics core to feature hardware shaders. All previous cores had the CPU perform vertex operations for them. That is why the new mobile chipset with the integrated graphics core can boast better performance and compatibility with 3D applications, in particular with the Microsoft Windows Vista Aero-interface. Intel also promises that X3100 will be compatible with DirectX 10, and released a new special driver recently.

The new graphics core works at 500MHz frequency and features 8 unified pipelines that can participate in 3D scenes rendering as well as in video playback acceleration. That is why X3100 also boasts hardware acceleration with video post-processing in MPEG2 and WMV9 formats (Intel Clear Video technology). However, the core doesn’t yet support newer formats such as Blu-ray and HD-DVD. We will have to wait for the next mobile platform refresh, then hardware acceleration of these formats may become available.

The table below offers you a detailed side-by-side comparison of the new and previous generation Intel cores:

While the performance has more than doubled, the new graphics core can also boast more advanced power-saving functions. They are primarily intended to make LCD panels more economical, because they are the main power consumers in mobile computers alongside with the CPUs. Intel X3100 features Display Power Saving Technology 3.0 that reduces the screen backlighting dynamically depending on the brightness of the displayed image. Moreover, Display Refresh rate Switching handles refresh rate reduction when the system is powered by battery.