2nd trinal Assignment

LPX / Mini LPX Form Factor

Without knowing it, retail PC customers have made LPX one of the most popular form factors of the last decade. Most PCs sold in slimline or "low profile" cases in the late 1980s and early 1990s use the LPX form factor, or a variant of it. Originally developed by hard disk manufacturer Western Digital Corporation back when they made motherboards, the goal of the LPX design was simple: to reduce the size and cost of the PC system box. The key design decision in LPX that enables the dramatic reduction of the size of the case is the creation of a riser card that plugs into the motherboard. Expansion cards then plug into the riser card, parallel to the motherboard. By doing this, the case no longer has to be tall enough to accommodate the height of an expansion card. See the discussion of the LPX motherboard form factor for more details on the LPX design.
One problem with the LPX form factor is that it is only a "pseudo-standard"; it was never formalized into a hard standard, the way for example ATX and NLX have been. Many companies make systems that use slimline cases and LPX-style motherboards and power supplies, but they often differ slightly in size, shape, or other characteristics. This means you cannot expect to move a power supply from say, a Compaq LPX system into a similar-looking Packard Bell system. LPX systems are essentially proprietary.
There is one innovation of the LPX form factor that has carried forward into the more modern designs: the use of integrated I/O connectors, and holes provided for them in the system case. The lack of this design in the Baby AT form factor led to increased cost and time of assembly, a problem avoided with the newer form factors.
LPX cases are usually used with LPX form factor power supplies, which are sometimes called "slimline" supplies because LPX systems are often referred to by their "slimline" style.




NLX Form Factor


NLX is Intel's proposal for the future of mass-marketed, retail PCs, replacing LPX. It is similar in overall design to LPX, with a riser card arrangement and low profile, slimline case. However, it has been updated and modernized to allow support for the latest technologies while keeping costs down. For a full description of the NLX form factor's characteristics and design goals, see the motherboard form factors section on NLX. You can also find detailed specifications about NLX and other newer form factors at the Platform Development Support Web Site.


Many slimline systems that were formerly designed to fit the LPX form factor are now moving over to NLX. One extra advantage of NLX over LPX is that it is a true standard, unlike LPX, making interchangeability of components more likely than it was for the older form factor. NLX seems destined to become of the most popular form factors in the PC world, complementing the ATX "family" of form factors.
The NLX specification does not define a new, specific "NLX" power supply form factor. NLX systems are intended to use ATX form factor power supplies.