The life and times of the modern motherboard

Posted at: Tuesday 27th November 2007 by Alex Watson

Ever wondered how a motherboard and its BIOS are designed and made? What makes one a brilliant overclocker and another as stable as a plate of jelly on a bouncy castle? Alex Watson investigates.

It isn't only the number of staff involved that makes motherboard design a major undertaking. It's a project in which every task is interlinked - after all, the BIOS needs to be written so that prototype boards can be booted and their functions verified. BIOS writers need to know what hardware will be on the board before they can write code to exploit it. And of course, much of the board's thermal engineering is dependent on how good an overclocker it will be. This in turn is determined by the BIOS and the hardware design.

No wonder Yu finds the development process a little tricky to explain. 'At the very beginning, everyone is involved so that we can define our goals and know what kind of hardware and BIOS options the project will require,' he says. After these initial meetings, each aspect of the project is handled by specialists. 'Hardware engineers and product managers get together to define the specs, the kind of things that need to be present on the board, which of these needs to be fitted and how they'll be placed. We also have a specific layout team that has extensive know-how concerning the tweaking of the layout. When you're figuring out the layout, you need to involve the thermal engineers and power engineers, as they need to know what kind of power designs they'll be using, and whether they can work with the elements that the electrical engineering guys want to place strategically. For example, they'll say, 'If you want to have the power sitting here, that means my thermal module will have to be fitted a certain way.' The product manager then becomes involved, saying 'We need this and that, so how do we arrange it?''

'Our hardware engineers also have a lot of knowledge about the schematics, traces and lines that each component needs. The strategy is how you make everything fit, and in such a way that it will yield maximum performance. How you arrange all these elements has a big influence on performance, so you have to figure out which way is the most economical and efficient, without causing interference,' says Yu. To help finesse the layout, and balance the input coming from the specialist engineers, both computer models and simple mock-ups are used. 'We have computer programs, but we'll sometimes carry out checks in the most basic, analogue way - we'll build a model. It's very similar to the process used when building cars - you create 3D models, but you also shape a piece of wood to see what the product is like in a real environment, and how it differs from simulations.' Once everything is in position, the layout needs to be tested to see if its electrical and thermal performance is as it should be.

At this point, the BIOS team will hopefully be progressing well with their first BIOS. 'At the beginning of the project, the hardware designers will give their specifications to us. We then implement the BIOS according to their design,' says Alex Perng. 'If the BIOS finds something wrong, we ask the hardware people to change their design so that the errors are fixed.'