Intel's X58 Express chipset is a big departure from the way Intel has designed their core logic for the past five or so years.

The biggest change is the removal of the Front Side Bus, which used to be the communications path that let the CPU, northbridge and memory send data to one another.

The replacement for the Front Side Bus is called Quick Path Interconnect, and it runs directly from the X58 northbridge to the Core i7 CPU. This new data interface reduces the amount of congestion and bottle necking that the FSB could cause in previous Intel chipsets. The QPI for Intel's X58 chipset can support up to 6.4 giga transfers/second per direction, for a total of 12.8GB/s of aggregate bandwidth.

So if QPI is connecting the CPU and the northbridge together, how is the memory communicating with anything? Well, Intel has taken a page from AMD's book, and has placed the memory controller on the processor, instead of making the northbridge responsible for it. This reduces overall memory latency and frees up system bandwidth.

Currently, for all of QPI's dramatic changes from traditional FSB-based architecture, it still operates very much like Intel's previous chipsets, and most won't notice that the memory controller has migrated. However QPI's nature as a point-to-point interface (instead of a bottleneck-prone all encompassing 'stream', the way FSB is), open up possibilities for it to be used in multi-processor systems, where two physical processors can be used on a single motherboard, both of them connecting to an I/O core logic chipset like the X58 simultaneously through a pair of QPI links. This is all in the future for desktop computers, although dual and quad-socket server boards designed for Nehalem-based Xeon processors are already starting to appear.

The Intel Core i7's memory controller supports DDR3 memory only, with official support for speeds of PC3-6400 and PC3-8500 memory (also known as DDR3-800 and DDR3-1066), optimized for triple-channel bandwidth. On certain motherboards like the MSI Eclipse Plus, it's possible to use faster DDR3-1333 memory. The total memory capacity for the Intel X58 Express chipset is 24GB.

An important note about DDR3 memory - watch the voltages! Running DDR3 voltages above 1.65v can cause permanent CPU damage over time. Since some DDR3 modules that were designed for older chipsets natively require higher voltages, it's wise to be very careful about memory choices when you're setting up an Intel X58 motherboard.

Intel Chipsets Feature Breakdown Intel X58 Express Intel X48 Express Intel X38 Express Intel 975X Express Intel P35 Express CPU LGA 1366 Core i7 LGA775 Core 2 Quad LGA775 Core 2 Duo LGA775 Core 2 Duo LGA775 Core 2 Duo Front Side Bus (FSB)/QPI 6.4 GT/S 1600/1333/1066/800 MHz 1333/1066/800 MHz 1066/800 MHz 1333/1066/800 MHz Intel XMP Memory Yes Yes Yes No No Memory Support DDR3 1066/800 DDR3 1600 (XMP) /1333/1066/800 DDR2 1066/800/667 DDR3 1333(unofficial)/1066/800 DDR2 800/667/533 DDR2 1066/800/667 DDR3 1333(unofficial)/1066/800 Maximum Memory Capacity 24GB 8GB 8GB 8GB 8GB Integrated Graphics - - - - - PCI Express 2.0 x16 2 2 2 2 1 PCI Express x1 6 6 4 4 6 Intel Matrix Storage Technology Yes Yes Yes Yes Yes SATA/IDE HDD 6/0 6/0 6/0 4/1 6/0 SATA Speed 3GB/s 3Gb/s 3Gb/s 3Gb/s 3Gb/s RAID 0, 1, 5, 10 (with ICH10R) 0, 1, 5, 10 (with ICH9R) 0, 1, 5, 10 (with ICH9R) 0, 1, 5, 10 (with ICH7R) 0, 1, 5, 10 (with ICH9R) Hard Drive NCQ Yes Yes Yes - Yes USB 2.0 Ports 12 12 12 8 12 PCI Masters 6 6 6 6 6 Audio High Definition Audio (Azalia) High Definition Audio (Azalia) High Definition Audio (Azalia) High Definition Audio (Azalia) High Definition Audio (Azalia)