Page 82 - A Practical Guide from Design Planning to Manufacturing

58 Chapter Two

In 1998, Intel began negotiations with Apple to begin including
FireWire support in Intel chipsets. FireWire would be used to support
high-performance peripherals, and USB would support low-performance
devices. Apple asked for a $1 licensing fee per FireWire connection, and
5
the Intel chipset that was to support FireWire was never sold. Instead,
Intel and others began working on a higher-performance version of
USB. The result was the release of USB 2.0 in 2000. USB 2.0 retains
all the features of the original standard, is backward compatible, and
increases the maximum bandwidth possible to greater than FireWire at
the time. Standard with Intel chipsets, USB 2.0 is supported by most
PCs sold after 2002.
Both USB and FireWire are flexible enough and low cost enough to
be used by dozens of different devices. External hard drives and optical
drives, digital cameras, scanners, printers, personal digital assistants,
and many others use one or both of these standards. Apple has contin-
ued to promote FireWire by updating the standard (IEEE-1394b) to
allow double the bandwidth and by dropping the need to pay license fees.
In 2005, it remains to be seen if USB or FireWire will eventually replace
the other. For now, it seems more likely that both standards will be
supported for some years to come, perhaps until some new as yet
unformed standard replaces them both.

Motherboards
The motherboard is the circuit board that connects the processor,
chipset, and other computer components, as shown in Fig. 2-5. It phys-
ically implements the buses that tie these components together and
provides all their physical connectors to the outside world.
The chipset used is the most important choice in the design of a mother-
board. This determines the available bus standards and therefore the
type of processor, main memory, graphics cards, storage devices, expan-
sions cards, and peripherals the motherboard will support.
For each chip to be used on the motherboard, a decision must be made
whether to solder the chip directly to the board or provide a socket that
it can be plugged into. Sockets are more expensive but leave open the
possibility of replacing or upgrading chips later. Microprocessors and
DRAM are the most expensive required components, and therefore are
typically provided with sockets. This allows a single motherboard design
to be used with different processor designs and speeds, provided they
are available in a compatible package. Slots for memory modules also
allow the speed and total amount of main memory to be customized.

5
Davis, “Apple Licensing FireWire for a Fee.”