Overview of the I9xx Architecture

To first understand what is happening here, we will give a brief description of the I9xx architecture. This won't be a complete run-down, as we have done this in our previous article here - instead it will give you the basic idea of what is available to us.

The I9xx series chipsets have a common feature set, varying slightly with each model. The top dog, so to speak, is the I925X. This chipset is designed for high-end systems with support for 533 and 800MHz FSB CPU's only. Since the Celeron D is now available on the 533FSB that means this chipset is Celeron D compatible. To add to this, a 16x PCi Express lane is added to the Northbridge to deliver 8GB/s 2 way traffic (4GB/s to and 4GB/s from) for the next generation video cards from ATI, nVidia and various other GPU manufacturers. This replaces the AGP specification completely, so we now have no AGP support on the I9xx boards.

Added to this is a 128bit wide DDR-2 memory controller. This controller is the first to market DDR-2 supporting chipset with support for DDR-2 400/533/667 memory. This allows in theory for up to 10GB/s memory bandwidth. The Intel I915 series also shares the DDR-2 memory controller; however, to make transition somewhat smoother, the I915 series also has a 128bit DDR memory controller as well which gives compatibility with existing DDR modules, reducing overall costs.

Intel has also coupled its new MCH with a brand new ICH, dubbed the ICH6. This controller has three variations - ICH6, ICH6-R and ICH6-RW. All share a common set of features with very slight differences, let's start with the common:

- Four Serial ATA ports are now supported with ACHI (Advanced Host Compliant Interface) protocol for Native Command Queuing and hot swapping. This is the first chipset to support Native Command Queuing, which should in theory speed up disk order and allow for a faster overall disk access.

- A new high quality audio codec called Azalia has been added. This new codec allows for up to 192kHz and 44Hz audio, similar to that of the Creative Audigy2 and VIA Envy24 audio controllers with support for 7.1 speaker configurations, without taxing the CPU anywhere near as much as the AC'97 audio once did.

- This ICH6 series has support for three PCI Express x1 lanes for 500MB/s bi-directional (250MB/s to and 250MB/s from) independent bus. This means each port gets 500MB/s rather than sharing like traditional PCI bus. PCI is also supported, with up to 6 PCI bus masters supported, so PCI compatibility is still maintained which is a good thing.

This is where the similarities end. The ICH6-R adds RAID support with the new Matrix Technology which allows for the four Serial ATA drives to act in RAID 0, RAID 1, RAID 0+1, JBOD or Matrix.

The ICH6-RW varies in that is has all the features of the ICH6-R with a built in Wireless Network controller on the Southbridge. This allows for a cheaper Wireless adoption for home users, businesses and mobile users when this Southbridge goes into mobile I9xx chipsets. All this is now added with a new Link called the Digital Media Interface or DMI which operates at 2GB/s between the MCH and ICH, allowing for a much improved data flow.

Now we have covered the basics of the new chipsets from Intel, let's continue on as we take a look at our first motherboard in the roundup.

Find the lowest price on Intel 915 and 925 Motherboards!