Intel 5 Series

Intel 5 Series is a computing architecture introduced in 2008 that improves the efficiency and balances the use of communication channels in the motherboard. The architecture consists primarily of a central processing unit (CPU) (connected to the graphics card and memory) and a single chipset (connected to motherboard components). All motherboard communications and activities circle around these two devices.

The architecture is a product of adjustments made to the Intel 4 Series to deliver higher performance motherboards while maintaining efficiency and low power. The changes revolve around chipset and processor design, in conjunction with a rearrangement of functions and controllers. The result is the first major change in many years of computing.

The concept of the architecture was to improve motherboard mechanics to keep pace with the CPU as it gained more speed and multiplied in number of cores. In the previous architecture, the CPU was communicating heavily with the motherboard's central component, the Northbridge chipset, as it was the intermediary between the CPU, memory, and, in most cases, graphics card. The CPU would communicate with the Northbridge chipset when it needed data from the memory or when it needed to output graphics to the display. This arrangement caused the communication channel known as the front-side bus (FSB) to be heavily used. It was not long till either the FSB would reach full capacity or operate inefficiently with more cores. With the memory controller and/or graphics core moved into the processor, the reliance of separate motherboard chipsets for these functions are reduced.

The Ibex Peak chipset includes only Platform Controller Hub (PCH) per model, which provides peripheral connections, and display controllers for CPU with integrated graphics via Flexible Display Interface (excluding P-models). Additionally, the PCH is connected to the CPU via Direct Media Interface (DMI).

Taking advantage of Intel Nehalem CPUs with integrated graphics and PCI Express ports, the Intel management engine (ME) and a display controller for integrated graphics, once housed in north bridge, are moved into the Platform Controller Hub (PCH). The I/O Controller Hub (ICH) function is integrated into the PCH, removing the need for separate north bridge and south bridge.

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