Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am confused about the following concepts and their relations: controllers, interfaces, adapters, chipsets, buses and north/south bridges. Can anyone point out how they are working together, what are their differences and relations?

Thanks and regards!

I attempt to picture the concepts as different places in a diagram of computer organization, but really can't.

share|improve this question
+1 this is actually a good question. A clear concise explanation of these concepts would be valuable. – Nifle Jun 5 '10 at 13:36
up vote 3 down vote accepted

A controller is just as it sounds. A circuit(s) that control a process. USB Controllers are responsible for controlling USB ports, for example.

Interfaces are places where components area connected. A SATA connection could be called an interface. NIC stands for Network Interface Card.

I don't know what you mean my "adapt cards" maybe you mean daughter boards or Adaptec cards? Adaptec is a manufacturer of computer components and a daughter board or riser board are used in servers and some odd form factor desktops to make interfaces available in non-natural locations given the layout of the motherboard.

A bus connects controllers to each other and to the CPU and to interfaces. Data travels on the busses from one place to another. This is how data gets from the hard drives to the RAM to the CPU to the video card, etc.

A chipset is a combination of controllers on the same piece of silicon. There are, traditionally, northbridge chipsets which handle high-speed connections like RAM, CPU and video and a southbridge chipset which handles slower operations like disk I/O, USB, PCI, etc. This is changing in modern designs however and some designs have a direct bus between the CPU and RAM and other major controllers are all being made on a single piece of silicon.

So for an example of how it all works together: When you plug a device like a USB drive into a USB interface, the USB controller that is probably located on the southbridge chipset interacts with the device over the bus. Any data that is needed is sent to the CPU for processing and if anything needs to be displayed on the screen as a result, the CPU will send data to the northbridge chipset which will be delivered to the video card for display to the monitor, which is probably connected to the computer by a VGA, DVI, HDMI, or Displayport interface.

share|improve this answer

If you read and follow links for the subcomponents I think that covers all your points except Not sure what you mean by adapt cards... adaptors? wireless adaptors? Sorry...

share|improve this answer
And post any specific Qs you have... – Andy Jun 5 '10 at 13:35
Hi Andy. Just FYI, it is frowned upon to post links and say "go read". I realize there was no rudeness involved, but the point of SU, SO, and SF is to collect a massive database of knowledge on the questions asked. There is no guarantee that those Wikipedia pages will say the same thing in 5-10 years or that they will even still exist. The proper way to answer a question like this would be to quote the relevant pieces from Wikipedia using the blockquote formatting and then at the bottom provide links to your sources for further reading. – MDMarra Jun 5 '10 at 13:50
Sorry, thanks :) – Andy Jun 5 '10 at 14:14

I mostly concur with MarkM's answer though i do want to explain a little bit more:


Controllers are usually integrated circuits that provide a specific function on the motherboard. for example, SATA (Serial ATA) controller provides connectivity to hard disk from the motherboard; USB controller provides connectivity to USB devices from the motherboard.


Interfaces are standards by which devices connect together. e.g. the harddisk connects to the harddisk controller via the SATA interface; and the SATA (harddrive) controller connects to the motherboard via "PCI-E" interfaces


Adapters has several meanings in a hardware context:

  1. Power adapters (another name for AC-DC transformers).
  2. Plug-change adaptors (e.g. change from DVI to VGA plug)
  3. Another name for plug-in cards e.g. ISA, PCI and PCI-E adapter cards, "VGA adapters", etc.


A combination of north and south bridges.


An interface for transfer of data inside computer. Examples are ISA, MCA, PCI, VL-BUS, AGP, PCI-X and PCI-E buses.

North/south bridges

Traditionally the northbridge is concerned with connecting the high speed devices e.g. RAM and graphics card. The southbridge handles the rest (e.g. hard disk, USB, printers, etc.) This distinction is changing, though, as sometimes the PCI-E controller and memory controller is moved to the CPU (note: i7-8xx series CPU).

share|improve this answer
A chipset is just a set of integrated circuits on the same silicon. North and southbridges are just specific examples. – MDMarra Jun 6 '10 at 18:54
You are very correct. Though chipset in our daily lives usually refers to those on the computer motherboard. – bubu Jun 6 '10 at 18:59

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.