Installing RAM and Motherboard
We install the DIMMs with the
motherboard and pan still out of the case. You
can see the two alignment notches in the contact
edge of the DIMM, and the two blocking keys in
the socket, so the DIMM will only go in one way.
The minor increase of static electricity risk
working outside the case is well worth getting
the DIMMs in without damaging them or the
The new style DIMM sockets have
one disadvantage vs. the older "lean in" SIMM
sockets. You need to apply a good deal of force
to make the DIMM engage the locking mechanism
and seat properly. Definitely a two thumb job.
Here we see the ATX motherboard,
mounted on the pan, ready for installation into
the case. The CPU (a Pentium II) and heatsink
havebeen installed, and the heatsink fan has
been connected to the motherboard. Two SDRAM
DIMMs, 32MB each, have been installed.
When installing the motherboard
pan (with motherboard, CPU and RAM mounted) back
in the case, you want to be very sure that you
don't accidentally crush any cables or onboard
components when moving the pan into place.
Normally, the pan hinges along one edge when
aligned properly. Don't procrastinate putting
the all of the screws attaching the pan to the
frame back in once the pan is positioned.
Once the pan is installed, the
motherboard is ready to be electrically
connected to the case power supply and drives.
You can see in the picture the extra mounting
holes in the pan for motherboards of a different
The 20 lead ATX power supply
connector replaces the P8 and P9 connectors of
the older AT power supplies. The connector is
keyed to go on one way, and is generally as easy
to install with the pan inside the case as out.
The ATX design usually leaves
enough room to attach all of the case LEDs
(lights) and switch leads with the motherboard
installed. LED and switch leads are often labled,
power, HDD (hard drive), keylock, right on the
leads, but if not, you'll have to follow them
back to the front of the case and read off the
faceplate what they are.
With the motherboard pan
installed in the ATX case, you can now see the
I/O core ports through the openings in the metal
I/O shield. Most case manufacturers provide a
metal bezel that fits around all of the ports,
providing RF shielding and pictorial or text
labels for the ports.
Next > Instaling Adapters and Configuration