Mylex MPE-PNTM, User Manual

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Chassis Installation
The MPE--PNTM is designed to fit “Full AT” style chassis.
Some chassis may have slightly off--set dimensions due
to manufacturing tolerances or design implementation.
Therefore, it is suggested that before the system board is
physically installed, the board be put into place to assure
proper fit. Note the locations where screws can be in-
stalled and where the nylon stand--offs can be used. For
proper grounding, at least two screws should be used to
lock the system down. These two locations are the most
commonly used points for screw mounting locations. If
more screw mounting locations are available, it is highly
recommended that they be used as well. See Figure 2--
1.
Once the locations for both the screws and the nylon
stand--offs have been identified, remove the board, insert
the nylon stand--offs, making sure all the stand--offs are
in their proper position and are not causing the board to
warp. Then install the board into the chassis. Then lock
the system board into place by installing the screws. Do
not over--tighten. Usually 1/8 turn after the screw--head
makes contact is sufficient to assure a good ground.
Note: In order to use all available slots (seven EISA, three
PCI), you'll need a “full--size 12--slot AT--sheet chassis.”
A tower chassis is recommended for better ventilation.
Important Note: The Pentium processor requires proper
cooling (forced air circulation) for reliable operation. J18
is used to supply 12 volts for a heat--sink fan. Ensure that
the heat--sink fan assembly is securely fastened onto the
Pentium System Board, and that the fan power cable (2
wire) is connected to J18. Usually the black wire is the
ground wire and the red/yellow wire is +12v.
Pin 1
(marked as +12V) pr12V input to the fan. If this
cable is inserted with the wrong polarity, the fan may not
rotate at all. After powering on the system, make sure the
fan is rotating properly.
Copyright 1994 Version D02 2 - 9
Installation MPE-PNTM System Board