North chipset vs south chipset - differences between the two

Northern chipset vs southern chipset: How can we identify them? The concept of chipset has become quite important over the years, especially when it comes to gaming equipment. Manufacturers launch their new CPUs and often come hand in hand with new chipsets and memory controllers. If you still do not know what we are talking about, in this article we will clear all doubts about these concepts, delving into the main characteristic of a motherboard: the chipset.

What is a chipset and what is its importance

The term chipset refers to a set of chips or an integrated circuit, capable of performing a number of functions. In computer terms these functions are related to the management of different devices connected to the motherboard and the intercommunication between them.

The chipset was always designed based on the architecture of the central processor, the computer's CPU. This is why whenever we talk about the chipset we should also talk about the CPUs that are compatible with it and the possibilities it offers us in terms of capacity and speed. Therefore, the chipset is the communications control and the chip or chips that are responsible for controlling the data traffic on the motherboard. We are talking about CPU, RAM, Hard Drives, PCIe slots and ultimately all the devices that can be connected to the computer.

At present we find two chipsets on a board, or rather, on board and processor, the north or north bridge, and the south or south bridge. The reason for calling them this way lies in their location on the board, the first one at the top closest to the CPU (north) and the second one below (south). Thanks to the chipset we can consider the motherboard as the main bus of the system. The axis that is capable of interconnecting elements from different manufacturers and of different nature in an integrated way and without incompatibilities between them. For example, an Asus board, with an Intel CPU and a Gigabyte graphics card.

Since the appearance of the first electronic transistor-based processors, 4004, 8008, etc., the concept of chipset appeared. With the advent of personal computers, the use of additional chips on the motherboard to manage RAM, graphics, sound system, etc. became popular. Its function was clear, that of reducing the workload of the main processor, deriving it in other circuits that in turn connected to it.

North bridge: functions and features

Intel G35 North Bridge

We will see the north chipset vs south chipset defining what they are and how each one works. We will start with the most important, which will be the north bridge.

The north chipset is the most important circuit after the CPU itself. Previously, it was located on the motherboard and just below it, using a chip almost always equipped with a heatsink. Today, the north bridge is directly integrated into processors from both Intel and AMD, the leading manufacturers of personal computers.

The function of this chipset is to control all the data flow that goes to or from the CPU to RAM, the AGP bus (before) or PCIe (now) from the graphics card, and also that of the South chipset itself. That is why it is also called MCH (memory Controller hub) or GMCH (graphic MCH), since many northern chipsets also had integrated graphics. So its mission is to control the operation of the processor bus or FSB (front side bus) and make the distribution of data between the aforementioned elements. Currently all these elements are embedded in a single silicon inside the CPU, but this was not always the case.

Evolution of the North Bridge

Internal architecture of the north bridge integrated into the AMD Ryzen 3000

Initially, both AMD and Intel boards and even other manufacturers such as IBM had these chipsets physically located on the board. Faced with the need to create integrated circuits that would take up little space and reduce the number of tasks for the processors, the only way was to separate them, and connect the CPU to it through the FSB.

Its complexity was almost at the level of the processors, so they also generated heat and needed heatsinks. Also, it was the only way to overclock the system. Instead of raising the CPU multiplier, what was done was raising the FSB multiplier, which today would be the BCLK or Bus Clock. Thanks to this, the bus ultimately went from 400 MHz to 800 MHz, causing the CPU frequency and RAM to rise as well.

The main reason that the main CPU manufacturers started to integrate this chipset within their CPUs was due to the latency it introduced. With processors already exceeding 2 GHz frequency, latency between RAM and RAM began to be a problem and a major bottleneck. Keeping these functions on a separate chip then began to be a disadvantage.

Intel started using a north chipset built into the CPU from the Sandy Bridge architecture in 2011 and the change of naming of its CPUs to Intel Core ix. Nehalem CPUs like the Intel Core 2 Duo and Quad still had a separate north bridge from them.

And if we talk about AMD, the manufacturer started using this solution from the first Athlon 64 processors as early as 2003 with HyperTransport technology to connect its north and south bridge. A manufacturer that started the x86 architecture with 64 bits and that would add a memory controller to its CPU long before its rivals.

South bridge: functions and features

AMD X570

The next element in the comparison of the north chipset vs. the south chipset will be the south bridge or also called ICH (input Controller hub) in the case of Intel and FCH (controller hub fusion) in the case of AMD.

We could say then that the south bridge is the most important chip located on a motherboard since the north bridge was relocated to the CPU. This is its first difference, since at present it is still installed on it and practically in the same position since its inception. This electronic set is in charge of coordinating the different input and output devices that can be connected to the computer.

We understand by input-output devices everything that is considered low speed compared to the RAM memory bus. We speak for example of USB ports, SATA ports, network or sound card, the clock, and even the APM and ACPI power management that is also managed by the BIOS. There are many connections to this chip, and the PCIe 3.0 or 4.0 bus also joins it, depending on the CPU generation.

The chipsets have acquired great power at the present time, with speeds that exceed 1.5 GHz, and need active cooling systems as in the case of the new generation AMD X570. The most powerful such as the aforementioned AMD and the Intel Z390, have up to 24 PCIe lanes in which to distribute the different connections of high-speed peripherals such as M.2 SSDs and other PCIe slots located in the expansion area of ​​the board.

This chip has been present since the beginning in 1991 with the concept of local bus architecture. In it, the PCI bus was represented in the center of the diagram, while upwards we had the north bridge, and downwards the south bridge, in charge of the "slower" devices.

Current South Chipset and its importance

The chipset not only manages the input / output devices on the board, but also plays a very important role in the compatibility with the CPU. In fact, in most cases, chipsets appear along with new CPUs released to the market, associating with their architecture.

This is not always the case, since both AMD and Intel have chipsets that are compatible with different generations of CPUs, although depending on the case, certain functions will be available or not. For example, the AMD X570 chipset supports PCIe 4.0 along with the new AMD Ryzen 3000. But if we put Ryzen 2000 on a board, which is also compatible, the bus will become PCIe 3.0. The same will happen with the speed of the RAM and its factory JEDEC profiles. This compatibility depends largely on the BIOS and its firmware, since it is ultimately responsible for managing the basic parameters of the different elements on the board.

Current Intel chipsets

Chipset	MultiGPU	Bus	PCIe lanes	information
For 8th and 9th generation Intel Core processors socket LGA 1151
B360	Do not	DMI 3.0 to 7.9 GB / s	12x 3.0	Current mid-range chipset. Does not support overclocking but supports up to 4x USB 3.1 gen2
Z390	CrossFireX and SLI	DMI 3.0 to 7.9 GB / s	24x 3.0	Currently more powerful Intel chipset, used for gaming and overclocking. Large number of PCIe lanes supporting +6 USB 3.1 Gen2 and +3 M.2 PCIe 3.0
HM370	No (laptop chipset)	DMI 3.0 to 7.9 GB / s	16x 3.0	The chipset most used currently in gaming notebook. There is the QM370 variant with 20 PCIe lanes, although it is little used.
For Intel Core X and XE processors in LGA 2066 socket
X299	CrossFireX and SLI	DMI 3.0 to 7.9 GB / s	24x 3.0	The chipset used for Intel's enthusiastic range processors

Current AMD chipsets

Chipset	MultiGPU	Bus	Effective PCIe lanes	information
For 1st and 2nd generation AMD Ryzen and Athlon processors in AMD socket
A320	Do not	PCIe 3.0	4x PCI 3.0	It is the most basic chipset in the range, geared towards entry-level equipment with the Athlon APU. Supports USB 3.1 Gen2 but not overclocking
B450	CrossFireX	PCIe 3.0	6x PCI 3.0	The mid-range chipset for AMD, which supports overclocking and also the new Ryzen 3000
X470	CrossFireX and SLI	PCIe 3.0	8x PCI 3.0	The most used for gaming equipment until the arrival of the X570. Its boards are at a good price and also support Ryzen 3000
For 2nd Gen AMD Athlon and 2nd and 3rd Gen Ryzen processors in AM4 socket
X570	CrossFireX and SLI	PCIe 4.0 x4	16x PCI 4.0	Only 1st gen Ryzen are excluded. It is the most powerful AMD chipset currently supporting PCI 4.0.
For AMD Threadripper processors with TR4 socket
X399	CrossFireX and SLI	PCIe 3.0 x4	4x PCI 3.0	The only chipset available for AMD Threadrippers. Its few PCI lanes are surprising since all the weight is carried by the CPU.

Summary of differences north chipset vs south chipset

By way of synthesis, we are going to break down all the functions of the two chipsets to make it even clearer what each one is dedicated to.

AMD Ryzen 3000 - X570 Architecture

North chipset current functions

With the passage of time, the functions of the north chipset vs. south chipset have been increasing in a rather surprising way. While the first versions integrated in CPUs only dealt with controlling the RAM memory bus, now they have expanded their options with the arrival of the PCI-Express bus. Let's see what all of them are:

• Memory controller and internal bus: these are still the main functions. For AMD we have the Infinity Fabric bus and for Intel we have the Ring and Mesh bus. A 64-bit bus capable of addressing up to 128 GB of RAM in Dual Channel or Quad Channel (chains of 128 or 256 bits simultaneously) with up to 5100 MHz in the case of the new AMD Ryzen 3000. Communication between CPU and south bridge: of course we have the communication bus between the CPU and the south bridge that we have seen. In the case of Intel, it is called DMI and it is in its version 3.0 with transfer speeds of 7.9 GB / s. For AMD, use 4 PCIe 4.0 lanes in its new CPUs, also reaching 7.9 GB / s. Part of the PCIe lanes: The current processors, or rather the north bridges, have the ability to route data directly from the PCIe slots. Capacity is measured in lanes, and can have from 8 to 48 Threadrippers. These go straight into PCIe x16 slots for graphics cards and even M.2 SSDs. High-speed storage devices: In fact, this is one of the functions, of the north chipset now. It handles part of the storage according to the design of the plate and its range. AMD always connects an M.2 PCIe x4 slot to its CPU, while Intel does the same for its Intel Optane memories. USB 3.1 Gen2 ports: We can even find USB ports connected to the CPU, especially Intel's Thunderbolt 3.0 interface. Integrated Graphics: Similarly, many current CPUs have integrated graphics or IGP, and the way to get them to the I / O panel of the board is through the internal controller with an HDMI or DisplayPort port. In this way we have the ability to play content in 4K 4096 × 2160 @ 60 FPS without problems. Wi-Fi 6: In addition, the new CPUs will integrate wireless network functions directly into their new chips, adding even more functionality with the new Wi-Fi standard working with the IEEE 802.11ax protocol .

Intel Core 8th Generation and Intel Z390 architecture

South chipset current functions

On the part of the southern bridge, we will currently have all these functions:

• Direct bus to the CPU: As we have previously mentioned, the north and south chipsets will be connected through a bus to send the relevant data to the CPU. Both Intel and AMD operate at a speed close to 8GB / s today. Part of the PCIe lanes: the other part of the PCI lanes that the CPU does not have are the south bridge, in fact, they will be between 8 and 24 depending on the performance of the chipset. In them, M.2 PCIe x4 slots, expansion PCIe slots and different high-speed ports such as U.2 or SATA Express are connected. USB ports: Most USB ports will go directly to this chipset, except in certain cases as we have mentioned before. Currently we are talking about USB 2.0, 3.1 Gen1 (5 Gbps) and 3.1 Gen2 (10 Gbps) ports. Network and sound card: two other essential expansion components will be the ethernet and sound network cards, always connected to this chipset. SATA ports and RAID support: Similarly, slow storage will also always be connected to the south bridge. The capacity ranges from 4 to 8 SATA ports. Also, it offers the ability to create RAID 0, 1, 5 and 10. ISA or LPC bus: this bus is still valid on current motherboards. To it we have connected the parallel and serial ports, in addition to the PS / 2 mouse and keyboard. SPI and BIOS bus: similarly, this bus is maintained, providing access to the flash storage of the BIOS. SMBus for sensors: temperature and RPM sensors also need a bus to send the data, and this will be in charge of doing it. DMA Controller: This bus provides direct access to RAM memory for ISA devices. ACPI and APM power management: Finally, the chipset manages part of the power management, specifically how the power saving mode works to turn off or suspend the system.

Conclusion about north chipset vs south chipset

Well, this article reaches this point in which we detail in detail what the north bridge and the south bridge consist of. In addition, we have seen its evolution and all the functions of each of them on current motherboards.

Now we leave you with a few hardware articles to continue learning:

If you have any questions or want to make a correction about the content, leave us a comment in the box. We hope you found it useful.