Installing Memory 

Adding more memory to your computer is not brain surgery. Even though it might 
sound intimidating to anybody who has yet to crack open the case of their PC, 
it is surprisingly easy. We'll show you in a few steps how to add RAM in just 
a few minutes. 

Note: We'll cover only the most common type of memory modules for home 
computers in this guide, SIMMs and DIMMs. 

Take It Off 

Unplug everything from your PC and put the case on a clean work surface, 
preferably in a well-lit area. Remove the cover. If you suddenly find yourself 
attacked by killer dust bunnies, this might be a good opportunity to use a can 
of compressed air to clean out the dust and cob webs. 

Safety First! 

Before you get up to your elbows into the case, keep in mind that you're 
handling sensitive electronic circuitry that can be damaged if handled 
improperly. The biggest enemy is static electricity, so be sure to touch an 
unpainted grounded piece of metal before proceeding. The safest way to stay 
grounded is to leave the powerchord plugged into the back of your PC, leave 
the other end plugged into a power strip, plug the power strip into a wall 
outlet, and turn the powerstrip off. This way there is no power going to the 
PC, but the PC is grounded, and touching an unpainted part of the case will 
dissipate any static electricity. 

Get any obstacles out of the way for unobstructed access to the motherboard. 
Depending on the type of case you have, you might have to temporarily remove a 
cable or two, or maybe even move a drive cage or power supply out of the way. 
A while back I was trying to install a memory upgrade in a extremely small 
proprietary PC. I had to remove the power supply, the CD-ROM drive, the hard 
drive, and the floppy drive just to get to the memory slot on the motherboard. 
Yikes! Hopefully your PC offers easy access. Make sure you remember what you 
unplugged or unscrewed from where so you can put it back when you're done. 

Identifying The Memory Slots 

First you need to figure out where to stick it. Look closely at your 
motherboard. Depending on what type of memory you have, you'll see one of the 
two following type of slots. 

The first type is for the older 72-pin SIMM-type memory. It is usually found 
in first generation Pentium or older AMD CPU machines. This type of memory 
needs to be installed in identical pairs, no mix'n'match. The two slots that a 
pair of SIMMs go into is called a Bank. Most motherboards have two banks/four 
SIMM slots. The motherboard should show some type of marking, labeling the two 
banks as Bank 0 and Bank 1. This is important to know as you'll see later. 

The second type is by far the most popular 168-pin DIMM-type memory. It is 
found in all newer Pentium II/III, Celeron, Athlon, Duron systems. This type 
of memory can be installed one stick at a time, and can often be matched with 
different types of DIMMs. Most motherboards offer two, three, or four DIMM 
slots. The slots a DIMM goes into should be marked on the motherboard as DIMM 
0, DIMM 1, etc. This is important to know as you'll see later. 

Installing SIMMs 

You need to be methodical when installing memory. First you should remove the 
existing memory modules. SIMMs are held in place by flexible metal clips on 
each end of the slot. Carefully push the metal clips outward until the SIMM 
pops free. These clips can be tough. If you can't do it with your 
fingertips/fingernails, try using a pointed plastic object to assist you, not 
a metal one! If you use a screwdriver tip and slip, you could ruin your 
motherboard. 

Grab the SIMM at the ends, angle it a little toward the motherboard and pull 
it out. Repeat this with each module until they are all removed. When you lay 
them aside, make sure you keep the pairs together/in order if you removed two 
pairs. 

Now it's time to install the new modules. Take a look at the modules. You will 
notice that they have a little cut-out at the bottom corner on one side. This 
will help you make sure that you insert them the right way. 

Insert the first module into the first slot of the first bank at a 45 degree 
angle, then carefully rotate it to a vertical position. Two plastic pegs on 
the socket will go through the two small round holes on each end of the SIMM, 
as the metal clips snap into place. If the pegs don't line up to enter the 
holes, the edge of the SIMM is not correctly seated in the slot. If you feel a 
little resistance, that's probably due to the tension of the metal clips. But 
if you feel a lot of resistance and it just doesn't snap into place, it might 
because of the cut-out, and you might have the memory modules inserted the 
wrong way. Repeat this with each module until they are all properly seated. 

Test It 

Now hook everything up again, but leave the cover off for now, so you can test 
it. After verifying all connections, turn the power on and watch the monitor 
carefully. If everything went well, you should see the initial BIOS screen and 
a counter which represents a memory test. Take a note of the final number of 
KiloBytes (KB). Don't be surprised if the number is actually a few thousand KB 
higher than expected. For example, if you installed two 64 MegaByte (MB) SIMMs 
for a total of 128MB, the number on the screen should be 131,072. That's 
because one MB is 1024 KB, and 128MB * 1024 = 131,072KB. If everything looks 
ok, you're all set. Put the cover back on and enjoy your faster PC. 

Optional: If you filled up only one bank with your new SIMMS, you can now try 
to install a pair of the old memory into the second bank and see if your 
computer likes it. 

But what if the upgrade didn't work? The most common problems after a memory 
upgrade are either a number of beeps or an incorrect display of installed 
memory. This is your BIOS telling you that it rejected the memory, most likely 
due to an incompatible memory type installed. Consult with your motherboard 
documentation and the vendor you purchased the memory from to find out what 
type of memory is correct for your machine. Just to be safe, remove the memory 
modules again, make sure that you indentified the memory banks correctly and 
started with the first bank, and that you seated them correctly - then give it 
another try. 

Installing DIMMs 

You need to be methodical when installing memory. First you should remove the 
existing memory modules. DIMMs are held in place by folding plastic clips on 
each end of the slot. Carefully push the plastic clips outward until the DIMM 
pops free. Grab the DIMM at the ends, and lift it straight up. Repeat this 
with each module until they are all removed. 

Now it's time to install the new modules. Take a look at the modules. You will 
notice that they have two notches at the bottom end. If you take a closer look 
at the memory slots on the motherboard you'll see that there are two 
corresponding ridges in the slot. This will help you make sure that you insert 
them the right way. 

Insert the first module vertically into the first DIMM slot (again, the order 
is important). Carefully apply even pressure straight down with your thumbs on 
the top of the memory module. The plastic clips normally pop into position all 
by themselves when you install the new module. But it sometimes helps to pull 
the plastic clips up and inward with your index fingers while pushing down on 
the top of the module until the DIMM snaps into the socket and the plastic 
clips snap into place. If you feel a little resistance, that's probably due to 
the tension of the metal contacts inside the memory slot. But if you feel a 
lot of resistance and it just doesn't snap into place, it might because of the 
notches, and you might have the memory modules inserted the wrong way. Repeat 
this with each module until they are all properly seated. 

Test It 

Now hook everything up again, but leave the cover off for now, so you can test 
it. After verifying all connections, turn the power on and watch the monitor 
carefully. If everything went well, you should see the initial BIOS screen and 
a counter which represents a memory test. Take a note of the final number of 
KiloBytes (KB). Don't be surprised if the number is actually a few thousand KB 
higher than expected. For example, if you installed one 256 MegaByte (MB) 
DIMM, the number on the screen should be 262,144. That's because one MB is 
1024 KB, and 2568MB * 1024 = 262,144KB. If everything looks ok, you're all 
set. Put the cover back on and enjoy your faster PC. 

Optional: If you still have free DIMM slots after your upgrade, you can now 
try to install an old memory module into the first free slot and see if your 
computer likes it. 

But what if the upgrade didn't work? The most common problems after a memory 
upgrade are either a number of beeps or an incorrect display of installed 
memory. This is your BIOS telling you that it rejected the memory, most likely 
due to an incompatible memory type installed. Consult with your motherboard 
documentation and the vendor you purchased the memory from to find out what 
type of memory is correct for your machine. Just to be safe, remove the memory 
modules again, make sure that you indentified the DIMM slots correctly and 
started with the first one, and that you seated them correctly - then give it 
another try. 


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