Platform Controller Hub


The Platform Controller Hub is a family of Intel chipsets, introduced circa 2008. It is the successor to the Intel Hub Architecture, which used a northbridge and southbridge instead, and first appeared in the Intel 5 Series.
The PCH controls certain data paths and support functions used in conjunction with Intel CPUs. These include clocking, Flexible Display Interface and Direct Media Interface, although FDI is used only when the chipset is required to support a processor with integrated graphics. As such, I/O functions are reassigned between this new central hub and the CPU compared to the previous architecture: some northbridge functions, the memory controller and PCI-e lanes, were integrated into the CPU while the PCH took over the remaining functions in addition to the traditional roles of the southbridge. AMD has its equivalent for the PCH, known simply as a chipset, no longer using the previous term Fusion controller hub since the release of the Zen architecture in 2017.

Overview

The PCH architecture supersedes Intel's previous Hub Architecture, with its design addressing the eventual problematic performance bottleneck between the processor and the motherboard. Over time, the speed of CPUs kept increasing but the bandwidth of the front-side bus did not, resulting in a performance bottleneck.
Under the Hub Architecture, a motherboard would have a two piece chipset consisting of a northbridge chip and a southbridge chip. As a solution to the bottleneck, several functions belonging to the traditional northbridge and southbridge chipsets were rearranged. The northbridge and its functions are now eliminated completely: The memory controller, PCI Express lanes for expansion cards and other northbridge functions are now incorporated into the CPU die as a system agent or package as an I/O chip
The PCH then incorporates a few of the remaining northbridge functions in addition to all of the southbridge's functions, replacing it. The system clock was previously a connection and is now incorporated into the PCH. Two different connections exist between the PCH and the CPU: Flexible Display Interface and Direct Media Interface. The FDI is used only when the chipset requires supporting a processor with integrated graphics. The Intel Management Engine was also moved to the PCH starting with the Nehalem processors and 5-Series chipsets. AMD's chipsets instead use several PCIe lanes to connect with the CPU while also providing their own PCIe lanes, which are also provdided by the processor itself.
With the northbridge functions integrated to the CPU, much of the bandwidth needed for chipsets is now relieved.
This style began in Nehalem and will remain for the foreseeable future, through Cannon Lake.

Phase-out

Beginning with ultra-low-power Broadwells and continuing with mobile Skylake processors, Intel incorporated the clock, PCI controller, and southbridge IO controllers into the CPU package, eliminating the PCH for a system in package design with 2 dies; one larger than the other, the smaller one being the PCH. Rather than DMI, these SOPs directly expose PCIe lanes, as well as SATA, USB, and HDA lines from integrated controllers, and SPI/I²C/UART/GPIO lines for sensors. Like PCH-compatible CPUs, they continue to expose DisplayPort, RAM, and SMBus lines. However, a fully integrated voltage regulator will be absent until Cannon Lake.

Ibex Peak

The Intel 5 Series chipsets were the first to introduce a PCH. This first PCH is codenamed Ibex Peak.
This has the following variations:
Langwell is the codename of a PCH in the Moorestown MID/smartphone platform. for Atom Lincroft microprocessors.
This has the following variations:
Tiger Point is the codename of a PCH in the Pine Trail netbook platform chipset for Atom Pineview microprocessors.
This has the following variations:
Topcliff is the codename of a PCH in the Queens Bay embedded platform chipset for Atom Tunnel Creek microprocessors.
It connects to the processor via PCI-E.
This has the following variations:
Cougar Point is the codename of a PCH in Intel 6 Series chipsets for mobile, desktop, and workstation / server platforms. It is most closely associated with Sandy Bridge processors.
This has the following variations:
In the first month after Cougar Point's release, January 2011, Intel posted a press release stating a design error had been discovered. Specifically, a transistor in the 3 Gbit/s PLL clocking tree was receiving too high voltage. The projected result was a 5–15% failure rate within three years of 3 Gbit/s SATA ports, commonly used for storage devices such as hard drives and optical drives. The bug was present in revision B2 of the chipsets, and was fixed with B3. Z77 did not have this bug, since the B2 revision for it was never released. 6Gbit/s ports were not affected. This bug was especially a problem with the H61 chipset, which only had 3Gbit/s SATA ports. Through OEMs, Intel plans to repair or replace all affected products at a cost of $700 million.

Whitney Point

Whitney Point is the codename of a PCH in the Oak Trail tablet platform for Atom Lincroft microprocessors.
This has the following variations:
Panther Point is the codename of a PCH in Intel 7 Series chipsets for mobile and desktop. It is most closely associated with Ivy Bridge processors. These chipsets have integrated USB 3.0.
This has the following variations:
Cave Creek is the codename of the PCH most closely associated with Crystal Forest platforms and Gladden or Sandy Bridge-EP/EN processors.
Patsburg is the codename of a PCH in Intel 7 Series chipsets for server and workstation using the LGA 2011 socket. It was initially launched in 2011 as part of Intel X79 for the desktop enthusiast Sandy Bridge-E processors in Waimea Bay platforms. Patsburg was then used for the Sandy Bridge-EP server platform launched in early 2012.
Launched in the fall of 2013, the Ivy Bridge-E/EP processors also work with Patsburg, typically with a BIOS update.
Patsburg has the following variations:
Coleto Creek is the codename of the PCH most closely associated with Highland Forest platforms and Ivy Bridge-EP processors.
Lynx Point is the codename of a PCH in Intel 8 Series chipsets, most closely associated with Haswell processors with LGA 1150 socket. The Lynx Point chipset connects to the processor primarily over the Direct Media Interface interface.
The following variants are available:
In addition the following newer variants are available, additionally known as Wildcat Point, which also support Haswell Refresh processors:
A design flaw causes devices connected to the Lynx Point's integrated USB 3.0 controller to be disconnected when the system wakes up from the S3 state, forcing the USB devices to be reconnected although no data is lost. This issue is corrected in C2 stepping level of the Lynx Point chipset.

Wellsburg

Wellsburg is the codename for the C610-series PCH, supporting the Haswell-E, Haswell-EP, and Broadwell-EP processors. Generally similar to Patsburg, Wellsburg consumes only up to 7 W when fully loaded.
Wellsburg has the following variations:
Sunrise Point is the codename of a PCH in Intel 100 Series chipsets, most closely associated with Skylake processors with LGA 1151 socket.
The following variants are available:
Union Point is the codename of a PCH in Intel 200 Series chipsets, most closely associated with Kaby Lake processors with LGA 1151 socket.
The following variants are available:
Lewisburg is the codename for the C620-series PCH, supporting LGA 2066 socketed Skylake-X/Kaby Lake-X processors.
Lewisburg has the following variations:
Basin Falls is the codename for the C400-series PCH, supporting Skylake-X/Kaby Lake-X processors. Generally similar to Wellsburg, Basin Falls consumes only up to 6 W when fully loaded.
Basin Falls has the following variations:
Cannon Point is the codename of a PCH in Intel 300 Series chipsets, most closely associated with Coffee Lake processors with LGA 1151 socket.
The following variants are available: