What's the difference between motherboard and chassis?

Question

there are chassis and motherboard products.

I want to know what's the function of them, and what's the difference?

Apart from the answers below, be aware that sometimes "chassis" is used to clarify that somebody is talking about a physical server, not a server that is a VM. — rackandboneman, Sep 28 '19 at 19:49

score 36 · Accepted Answer · answered Sep 27 '19 at 22:14

36

Chassis

The chassis, also often called the "case", is the container or enclosure that holds all of the other pieces of a computer. It might include some switches, fans, and indicator lights. Desktops and servers will each use a chassis of a different size and shape, but the functions are similar.

Empty server chassis:

Empty desktop chassis:

Motherboard

The motherboard is a circuit board containing slots or sockets for the CPU and memory, and also contains supplementary circuitry. The motherboard will often have networking, video, and audio components built in, and it will usually have expansion slots for additional components to be added or upgraded. Motherboards are mounted in the chassis, typically in the largest open space you see in these pictures. The other open spaces are for other components, like fans, hard drives, and optical drives.

Server motherboards are similar to desktop motherboards, but usually are larger, and are capable of containing more CPUs and more RAM.

Server motherboard:

Desktop motherboard:

answered Sep 27 '19 at 22:14

Doug Deden

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+1, But i think just for the sake of better presentation of a server motherboard i would recommend a picture like [this](https://c1.neweggimages.com/NeweggImage/ProductImage/AE25_131492319745307741Ge32OIl5UW.jpg). The server motherboard you have choosen for example is almost indistinguishable from workstation, or gaming motherboards. – Soorena Aban Sep 28 '19 at 07:23
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@soorena12: The server motherboard example has noticeably different I/O from the desktop example... 5 ethernet ports instead of one, no audio. That really sets it apart from workstation boards more than say multiple CPU sockets. – Ben Voigt Sep 29 '19 at 05:54
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Well to my somewhat untrained eye they look the same @Ben Voigt :) – Jpe61 Sep 29 '19 at 17:01
Chassis also includes the power supply... and then there are blades. – Anthony X Sep 29 '19 at 20:11
How about a picture like this http://www.techxury.com/image/cache/data/motherboard/supermicro_motherboard_x10drw-it_top_techxury-700x700.jpg becuse it shows that server boards may be custom-fit for specific chassis, much more so than generic PCs. – Criggie Sep 30 '19 at 01:11
A case might also be called a housing... and my desktop motherboard indeed looks alike that server motherboard... some more CPU sockets would make the difference more obvious. – Martin Zeitler Sep 30 '19 at 01:47
@AnthonyX: None of the chassis I've used in the past decade have power supplies. DC-DC is either on motherboard (barrel socket) or on an ATX-connector-sized PCB, and AC-DC is an external brick with ~18V output. :-) – R.. GitHub STOP HELPING ICE Sep 30 '19 at 02:16
@Jpe61 to casual examination uniprocessor server boards and desktop boards do have a lot in common in that they're using the ATX (or a related smaller/larger variant) layout. It's only when you go beyond entry level servers to multi-socket boards like the one soorena12 suggested or long skinny boards from [blade enclosures](https://images.esellerpro.com/2131/I/118/714/Images%20003.JPG) that you end up with significantly different appearances. – Dan Is Fiddling By Firelight Sep 30 '19 at 02:17
@BenVoigt You are currect, i never said that picture does not show a server motherboard, but when i wrote my comment i had this statement in Answer in mind: "Server motherboards are similar to desktop motherboards, but usually are larger, and are capable of containing more CPUs and more RAM" so i thought maybe the picture i suggested was slightly more appropriate given the answer, I mean i studied hardware engineering and you too also know your motherboards but i think when answer is going for more CPU and RAM as characteristic of server motherboards we should show a picture of such board. – Soorena Aban Sep 30 '19 at 05:31

score 6 · Answer 2 · answered Sep 27 '19 at 15:22

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The chassis is the unit that houses the motherboard and other internal components.

The motherboard is the... motherboard. It goes in the chassis.

answered Sep 27 '19 at 15:22

joeqwerty

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I think for this especially, a picture is worth a thousand words – Mooing Duck Sep 27 '19 at 23:24

score 3 · Answer 3 · answered Sep 27 '19 at 15:35

The chassis is a housing and sometimes, especially for servers, comes with pieces of printed circuit board that connect individual components of the computer, for example power supply and mainboard.

The motherboard / mainboard of the computer is a device that is needed mostly for it's interconnection functionality. It offers a slot where the computer's processor is inserted, if it is not directly soldered to the board, and slots where random access memory (RAM) modules are inserted. Furthermore, it contains the chipset, which helps individual components of the computer to communicate with each other and a helps with starting up the computer. The mainboard also often provides connectors for peripherals, such as a monitor and mouse and keyboard.

The motherboard then is installed in the housing along with other components to create a fully functional and modular PC.