Grantsdale/Alderwood In Detail
This is Intel's vision on 2004's computers
One of the first noteworthy changes is the revised interface between the northbridge (GMCH - Graphics and Memory Controller Hub) and the southbridge (ICH - I/O Controller Hub). The speed of this interface, called HI 1.5, had to be increased because its bandwidth is limited to 266 MB/s. The new interconnect is called Direct Media Interface (DMI) and is supposed to be significantly different: According to Intel, older southbridge components (i.e. ICH5 for cost reasons) cannot be used here.
DMI is a point-to-point connection and runs at a clock of 100 MHz. Its performance amounts to 1 GB/s per direction. Right now, there are no attempts to link northbridge and southbridge via a non-proprietary serial protocol such as PCI Express (or HyperTransport in the case of AMD system components).
The buzzwords of Intel's new chipsets are Wireless LAN (802.11 a/b/g), Dolby Pro Logic IIx support (including automatic audio jack remapping in order to do away with searching for the right jack), Intel Extreme Graphics 3 with DirectX9 support (without vertex shaders), plus a dual display option.
Northbridge: Product Strategy Remains Unchanged
The 875P is to the left, the Alderwood is on the right. The die size is not very different: 102 respectively 109 mm2.
It is obvious that Intel will continue to use its successful strategy with the new chipset family. Intel will replace the Springdale with the Grantsdale while the Alderwood will succeed the Canterwood. Just the backdoor that enabled motherboard makers to run 865PE chipsets with the memory acceleration technique (PAT) of 875P won't be available.
However, there is only one essential difference between both chipsets. While the Grantsdale will both support DDR and DDR2 memory, the high-end model Alderwood will run with DDR2 only. Neither will have an AGP interface. Independent from the transition to PCI Express, this is a smart move, as customers are given the option to use the integrated Intel Extreme Graphics for the time being, while further elevating Intel's respectable market share in this area: A G-version of the new chipset series will be available to serve the value market.
Other news concern the network interface: While gigabit Ethernet adapters have been attached via the specifically introduced CSA interface with 875P and 865PE, the Alderwood and Grantsdale chipsets will implement GbE-support via PCI Express.
With all the technological changes, Intel will drop the 800 model numbering and switch to a higher number range, while keeping the proven nomenclature.