LPX and mini-LPX boards are conventionally used in mass-produced retail systems because of their use of a riser card that holds the expansion slots. This allows the board to be placed into many of the "name brand" slimline or low-profile cases. The downfall of this system is that you are usually limited to only two or three expansion cards. The video display adapter card is also built into the motherboard, saving the manufacturer money if the card is of good quality. However, if you want to upgrade to a new video card, this can cause problems unless the onboard video card can be disabled.

The NLX form factor is to LPX what ATX is to AT: Upgrades and improvements make it more suitable for modern PC technologies. NLX has the same overall design intent as the LPX, but it has a smaller footprint and an expansion card riser. It allows for larger memory modules, DIMM memory packaging, support for newer processor technologies, better thermal characteristics, more optimal CPU location, and flexibility in how the board can be set up and configured. Like the LPX, the NLX form factor is designed primarily for commercial PC makers producing machines for the retail market.

You should choose a motherboard based on the size constraints of your system and what performance you want to have. The board should have the correct processor slot for the chipset you've purchased, enough memory slots of the correct type (DIMM [dual in-line memory module] or SIMM [single in-line memory module]) for your memory requirements, and integrated cache or cache sockets for level 2 cache. Most peripherals (sound card, extra USB ports, network cards, etc.) require I/O bus slots on the board. Your board should have enough ISA (Industry Standard Architecture), PCI (Peripheral Component Interconnect), and AGP (Accelerated Graphics Port) slots to accommodate your peripherals, which may become difficult if you're using one of the smaller-footprint boards. You should also look at power requirements, connection ports, voltage regulation, and keyboard and mouse connection ports associated with your board and peripherals before beginning installation.

2) After you have selected your board, there are a couple of things you should do before beginning your installation. You should check the documentation of the board you've purchased. Documentation should include general information about the model number of the board and the manufacturer's contact information. The documentation should also include assembly instructions, configuration information, and a BIOS (Basic Input/Output System) manual. These are extremely important.

Instructions should include information on how to install, jumper, and configure the board; generally, the more information, the better. Information on acceptable processor and memory configurations for your board will help you select performance accessories for your PC. BIOS information will explain the settings, what they mean, and how to set up your board. Typically, the inclusion of these parameters are less important than the others, since BIOS information can typically be found on the Web.

3) Before installation, you should also check for the included hardware. Parts that typically accompany a motherboard are a floppy cable, IDE (Integrated Drive Electronics) cable, serial port connectors, a driver disk, a PS/2 mouse connector, and a parallel-port connector. The board you choose may have any combination of these and other cables not listed, depending on what is integrated with your board and what kind of a package you've purchased. These cables are not entirely universal. That is, it is not always advisable to use older cables with a newer motherboard or swap boards among machines without changing cables.

4) Now that you've checked your hardware and the instructions, you're almost ready to physically install the board into your PC. It will make life easier if you configure your board before installing it because you will not have to work within the confines of your case. You will make these changes by altering the configuration of jumpers, which are usually a combination of two pins and a small rectangular shunt used to short the pins together.

Warning: This is not a difficult task if you've got a pair of needle-nosed pliers or long fingernails and a list of the jumpers and settings for your particular board and needs; however, setting jumpers incorrectly can lead to permanent damage to hardware or data loss. Make sure you know what you're doing before you start. Once you've made a change, double-check it. It may seem like a waste of time, but it will save you time and money if it prevents you from frying your motherboard.

The reference material that came with your board will describe which jumpers you can change, where they are located, and what effect changing the jumper will have. First, change the processor voltage jumpers. The manual will tell you what settings you need for the core voltage of the CPU and the external (I/O) voltage, but if you are using an older processor with split-rail voltage, both settings are the same.

The speed of your processor is determined by two jumper settings: the bus speed and the multiplier. You might not be able to change these settings, as some manufacturers hard-wire the settings onto the board. Your manual will tell you whether or not you can change these settings.

If you are going to be using cache in a configuration different than standard, you will need to change the jumpers depending on how much cache is on the board and whether it is inserted or soldered to the board. Many chipsets have their own integrated cache, so this setting may be unnecessary. Check your manual to be sure.

Check the flash BIOS jumper if your motherboard has one to be sure that it is disabled. This should be the default. Check your manual.

If your system has a jumper to let you clear the contents of the CMOS (complementary metal-oxide conductor) memory, which is needed when a system password is set and forgotten, you will need to set the CMOS Clear jumper to normal or default or you won't be able to change your BIOS settings.

Unless you will be using an external battery to power your CMOS memory, you will need to make sure that the Battery Source jumper is set to the default position, which allows the on-board battery to power the CMOS memory.

Some motherboards allow you to enable or disable parts of the board at a hardware level, such as the serial/parallel ports or the floppy disk controller. Normally, you won't want to change any of the Disable jumper settings, but check them just to be sure.

Very rarely, you will need to change the Memory Size jumpers to set the size of the system memory. If your manual says you need to, do it.

Finally, double-check everything again, if only to spare yourself headaches later. Now, you're ready to begin the physical installation of the motherboard into the case. This can be a difficult procedure, and you can cause damage to your system if you're not careful (for example, by trying to plug the power cables into the board the wrong way). There are differences between boards of the same form factor and cases, so the information that follows might not pertain to your situation 100%; however, it should be close. Most connections are unidirectional, which means that they will not fit if they're not in the proper orientation, so don't try to force a connection.

5) There is some simple hardware that you'll need to be aware of to complete the installation: plastic standoffs, metal standoffs, screws, washers, plastic faceplates, and metal expansion slot covers.

Plastic standoffs (also called spacers and sliders) are white plastic connectors that have a round disc on one end and a collapsible point at the other. They are used instead of screws to attach your motherboard to the case. Metal standoffs are 3/16" hexagonal nuts with a threaded end that are typically made of brass or steel and connect to threaded case holes. Screws and washers are used to attach the board to the metal standoffs mentioned above, and also to space the metallic screws from the printed circuit board to avoid short circuits across your board.

Plastic faceplates (or bezels) are used to cover drive bays that are not in use. They help keep foreign material out of your case and help direct air flow around your heat-producing components. Most cases come with expansion slot covers that screw into place; however, if you've chosen to save some money on a case, you might find that the expansion slot covers are stamped into the sheet metal and cannot be replaced once they've been removed. If you've got the latter, make sure you're punching out the right cover before you've got a Swiss-cheese case.

6) You will need to be very careful to line up your board with the proper anchor points. If you bump the board, you could damage the hardware and ruin your investment. You will most likely need a Phillips-head screwdriver, the mounting hardware included with your board, wire snips and a, 3/16" hex driver or needle-nosed pliers. You should also have your case as open as possible (all of the panels off), so that you can get into the tight spots to attach the last few screws. If your case is small and confined, you might want to install your processor and some of the lower-profile components (memory, etc.) into the board now to avoid the hassle later, but only do this if you're going to be very careful while installing your board. You don't want to crack a stick of memory or your processor and ruin both components.

7) Arrange your case so that the expansion card slots and connectors are farthest away from you and locate the mounting holes in both the case and the motherboard. The mounting holes on the motherboard are usually in something resembling the following arrangement: one row of three or four holes along the back of the board where the expansion slots are, a second row of two or three holes (not necessarily in a straight line) in the middle of the board and a third row of two holes along the front edge of the board. Your case will either have threaded holes, in which case you will be using metal standoffs, or oblong slots about an inch in length, which use plastic standoffs.

8) Next, you should orient the motherboard to match the mounting holes in the case so that the holes in the board are roughly aligned with the holes in your case. Any connectors in your board should align with corresponding holes in your case, including mouse, keyboard, and expansion slots. Some mounting holes may not line up at all. This is OK because motherboards are almost invariably different from the nominal form factor. The back and middle holes will almost always line up. You should make sure that six or seven of the mounting holes match up to ensure that your board is fixed in place and will stay that way.

9) After you're sure that the motherboard will line up with the mounting holes in your case, you should install the metal or plastic standoffs in the appropriate places, screwing the metal standoffs into the case with the 3/16" driver and inserting the pointed end of plastic standoff into the holes in the motherboard. If you have one or two holes that do not match up to a hole, a handy trick developed over the years is to cut the disc off of a plastic standoff so that the standoff will help support the motherboard in the case.

10) Once your mounting hardware is attached to the board or case, align the board appropriately. You can line the board up with the metal standoffs directly if your setup does not require plastic standoffs; however, if you will be using some or all plastic standoffs, you need to line up the discs of the plastic standoffs with the wide part of the mounting slot in the case before sliding the board toward the narrow part of the slot. Once the board is locked onto the plastic standoffs, the holes for the metal standoffs should line up correctly.

11) If the heads of the mounting screws are large enough to overlap any circuitry on the motherboard, you need to use paper or plastic washers to prevent a short-circuit. Install washers if necessary and tighten down the mounting screws, being careful not to overtighten, as this can crack your board. At this point you can reinstall the motherboard mounting panel if your case is so equipped; otherwise, you're done with the installation of the board.

Before reconnecting your peripherals, you should check that the board is level in the case, that no part of the board is touching anything other than the standoffs (this includes underneath the board, if possible), and that the board is rigidly in place. You should also double-check fit and alignment so that your peripherals will install correctly.

12) Now that you're done installing the board, you have to reinstall your peripherals. You will need to connect the power connector(s) to your board. For an AT board, there will be a pair of six-wire cables coming from the power supply that go into the 12-pin power connector on the board. The four black wires go together in the middle of the row of 12 pins. For an ATX board, there will be a single cable with up to 20 wires in a 10x2 rectangular configuration and a keyed connector. Connecting this cable in the wrong orientation is difficult without forcing the connection. Connecting the power cables in the wrong orientation in an AT board is catastrophic, so be careful.

13) Attach the four-wire power cables from your power supply to the CPU fan and wire the power and reset switches to the board. Some newer PCs don't have reset switches, so you will have to refer to your instruction manuals to determine your course of action if this is the case. Some PCs will also have various LEDs (light-emitting diodes) that you might need to attach. Again, refer to your included reference materials.

14) Unless you were brave enough to pre-install your processor, memory, or various cards, now's the time to do that, referring to the instructions included with the various hardware.

That should do it. This reference was by no means exhaustive, but hopefully it has helped steer you in the right direction.

by David Miller