How much effort goes into designing and laying out a PC motherboard? [closed]

Question

How much effort goes into designing and laying out a PC motherboard? By this, I do not include Intel's IP etc, but I do including having to read all the documentation concerning the chipsets. And getting it to work, if not 100% tested

Answer 1

For a point of reference developing a reference design for a dual processor server type motherboard typically consumes the efforts of:

1. Three or four board design engineers who own the design and guide its way through development. Testing and verification of the electrical design is part of this work.
2. Four signal integrity engineers performing simulations on board stackup and waveform analysis for busses like DDR3, PCI3, USB, SATA, SMBUS, RMII, CHipSet Busses etc.
3. Two CAD engineers working board layout for a 8 or 10 layer board.
4. One or two mechanical engineers working on packaging, cabling and other mechanical details including board outline, mount holes and heatsinks.
5. One regulatory engineer who owns taking the board through emissions, immunity and safety testing.
6. One or two manufacturing and test engineers to review the design and assure that it meets the needs for high volume manufacturing.
7. One product development manager who owns the project schedule and manages the budget.
8. One or two BIOS engineers that support adapting a reference BIOS to the specific requirements of the board/system.

Expect the average design to require two re-spins. Through this process expect the board design engineers to be involved for 10 to 16 months. Other disciplines will be involved for lesser amounts of time.

This also assumes that the boards are built by a contract manufacturer that provides support to procure parts.

Not included here is the team of people that would be involved with validating the design from a performance and system functionality standpoint including the OS compatibility.

Answer 2

I feel that I should mention standardized computer-on-modules (COMs), which take almost all of the headache out of designing your own motherboard (if that is your goal). These are basically nearly complete computers where you just need to design a carrier board to expose the functionality you're interested in.

As an example, I just designed a carrier for a COM Express mini module. My carrier exposes a single 1xPCIe, Gb ethernet, USB, I2C, SPI, GPIO, and HDMI (and power, of course). I was able to do all of this on a four-layer PCB, which ended up costing me $800 for 25 boards (which really isn't bad at all). I assembled everything myself (parts costing about ~$40 per board, plus $375 for the COM itself), but you can pay more to have the board house do that for you.

It took me about a week and a half to design my carrier board, and the great thing is there are several vendors selling the form factor I chose, so I can switch if needed.