Hardware Reference
In-Depth Information
you should be able to replace one NLX board with another from a different manufac-
turer—something that was not possible with LPX.
The main characteristic of an NLX system is that the motherboard plugs into the riser,
unlike LPX where the riser plugs into the motherboard. Therefore, the motherboard can
be removed from the system without disturbing the riser or any of the expansion cards
plugged into it. In addition, the motherboard in a typical NLX system literally has no in-
ternal cables or connectors attached to it! All devices that normally plug into the mother-
board—such as drive cables, the power supply, the front panel light, switch connectors,
and so on—plug into the riser instead (see
Figure 4.8
). By using the riser card as a con-
nector concentration point, you can remove the lid on an NLX system and literally slide
the motherboard out the left side of the system without unplugging a single cable or con-
nector on the inside. This allows for unbelievably quick motherboard changes; in fact, I
have swapped motherboards in less than 30 seconds on NLX systems!
Figure 4.8
NLX motherboard and riser combination.
Such a design was a boon for the corporate market, where ease and swiftness of servicing
is a major feature.
As with most of the form factors, you can identify NLX via the unique input/output (I/O)
shield or connector area at the back of the board (see
Figure 4.9
). You only need a quick
look at the rear of any given system to determine which type of board is contained within.
Figure 4.9
shows the unique stepped design of the NLX I/O connector area. This allows
for a row of connectors all along the bottom and has room for double-stacked connectors
on one side.
