We'll start off with our standard skinny about the X58 chipset. As you guys learned through our previous articles, there are some distinctive new features about the Core i7 processor that make some challenging new design features for the mainboard. We explained in the Core i7 article that QuickPath replaces the Frontside Bus (FSB) and Northbridge combo. What you need to be aware of is that it also takes over the role of allowing the CPU to communicate directly with other system components, busses and controllers such as the PCI Express controller and DDR3 memory, which is not only a physical, but also a fundamental change in architecture.

This also changes our concept and understanding of the system clocks. All motherboard busses and components are driven from a single 133.33 MHz base clock. The resulting component speed values are generated by applying a multiplier value to this base clock.

Examples:

• CPU speed -- When multiplied by the system base clock speed (default 133.33 MHz) gives the CPU frequency. Four multipliers are used to define different speeds based on the number of active CPU cores. But a Core i7 965 processor is driven like this: 133.33 MHz x 24mp = 3.2 GHz, fairly easy to understand we think.
• Memory speed -- When multiplied by the system base clock speed gives the memory frequency. For example a Memory Multiplier of 10 times the base clock of 133.33 MHz results in a memory frequency of 1333 MHz.

Since that Core i7 processor communicates directly with memory, the controller is now located into the CPU and no longer in the motherboard chipset. This required an additional set of inter connections to the motherboard.

Though we all learned to love Socket LGA 775, it just doesn’t have enough pins for that CPU based memory controller, so this is the main reason why Socket LGA1366 is introduced. The socket is called LGA1366, and as you can always decode from the name pretty easily, has 1,366 pins and thus connections to the motherboard.

Read this well: if you purchase a Core i7 processor, then you will have to purchase a new mainboard as well as the two sockets are not compatible in any way shape or form. Intel’s X58 chipset therefore, is the first (and currently only) chipset to support this processor. There is however a horrible rumor that yet another LGA socket will surface later in 2009, socket, LGA 1160 for mainstream processors. We feel this is getting a bit tricky, and hopefully Intel will stick to just one new Socket, Socket 1366.

Crossing the Southbridge

So we have the X58 chip "Northbridge" on that motherboard covering all the primary functions, but what about secondary lower level functions. Well, Intel will pair the motherboard with the ICH10 or the ICH10R "South bridge" similar to the Intel P45 (Eaglelake) chipsets.

ICH10(R) implements a 10Gb/s bidirectional DMI interface to the X58. ICH10 is basically a die-shrink of ICH9, boasting similar specs. It supports several interfaces to the somewhat slower peripherals on your motherboard like SATA and USB:

• Six PCIe version 2 ports, four of which can be configured as either 4x1 or 1x4
• Six SATA 3Gb/s ports in either legacy IDE or AHCI mode. These can support external eSATA
• One PCI slot
• Intel high definition audio
• Integrated gigabit LAN.
• Six USB 2.0 controllers 12 ports