Upgrading Memory (RAM)

Before beginning the procedure for replacing RAM, let’s first discuss its features and characteristics and what purpose it serves.

There are two types of information storage on your computer: primary and secondary. Primary storage is provided by devices referred to as memory or more specifically, Random Access Memory (RAM). Secondary storage is provided by such devices as hard drives, floppy drives, and CD-ROM drives.

There are distinct differences between primary and secondary storage. For example, secondary storage is also known as permanent storage, since the information stored on these devices is saved in such a way that it is available for later retrieval.

You can open an application, create and save a document, turn your computer off, and be able to retrieve that document at a later time. That is, when power is removed from the device, the information does not disappear. This is what is often referred to as non-volatile memory.

RAM, on the other hand, is volatile – when power is removed, the contents of the RAM memory chips are lost. We’ve all experienced this at one point or another (has your computer ever locked up just before you saved those latest changes, requiring a reboot or full shutdown?). Because the information in RAM is lost when power is removed, RAM is known as temporary storage.

The advantage that primary storage (RAM) has over secondary storage (hard drive) is that it is much faster. There are a few reasons for this. One is that RAM modules, which plug directly into the motherboard, are purely electronic devices. There are no moving parts. Electromechanical devices such as hard drives and CD-ROMs, with their motors, spinning platters, read-write heads, and so forth, take much longer for the CPU to access.

Secondly, because RAM is simply plugged into the motherboard, it is much closer to the CPU than secondary storage devices, which are mounted to the case and connected to the motherboard via an awkward and sometimes lengthy cabling system.

Furthermore, the communications bus for RAM modules is much wider than that of a secondary storage device, meaning that it can move a lot more data in one fell swoop than a secondary storage device is capable of.

So in a nutshell, here’s what happens. When you run a program such as a word processor, the computer pulls the executable file from the hard drive and loads it into RAM, where processing operations are faster. Some additional support files are also loaded, such as DLL (dynamic link library) files, which are shared pieces of code used by multiple applications. The data file you want to work on is also loaded.

Remember also that most computer users have multiple applications open simultaneously. In addition to the word processor, you may also have opened an email program, a graphics editing program (e.g. Paint or Photoshop), and several Internet browser windows.

Modern software applications are very large and complex programs, making them very ‘memory-hungry’. And many websites these days are multimedia in nature, incorporating not just text, but graphics, sound, and video – all of which take up a lot of space in memory. The operating system itself is also loaded into memory, which also takes up a fair amount of space.

When the amount of space needed in RAM for all the open programs exceeds the space available, a ‘swap file’ is created on the hard drive, and information is shuttled back and forth between RAM and the hard drive. This process is managed by a ‘virtual memory manager’, which may notice, for example, that you haven’t used your email program for awhile, and so the email program is swapped out to the hard drive to make room for another program you want to open.

This swapping out of information back and forth between RAM and the hard drive can cause a noticeable delay. So one of the major reasons for adding or upgrading RAM to your computer is to speed up operations. The other reason would be if one of the RAM modules has failed. Either way, there are some technical issues that must be taken into consideration.

First of all, it’s helpful to know how much RAM is installed in your computer. There are a couple of ways you can find out. The easiest way is through Control Panel.
Here’s how to check In Windows XP:

  1. Go to Start > Settings > Control Panel
  2. Double click the System icon to open the System Properties window
  3. Select the General tab
  4. The amount of RAM is shown in the Computer section of the System Properties screen

And in Windows Vista:

  1. Go to Start > Control Panel
  2. Click the System and Maintenance icon
  3. Click the System icon
  4. The amount of RAM is shown in the System section of the System window

There are several different kinds of RAM, including the older SDR (single data rate) SDRAM (synchronous dynamic random access memory) found on computers prior to 2002, and DDR (double data rate) SDRAM, which became mainstream around 2002. DDR2-based systems hit the market in 2004, and this type of RAM is able to operate at faster bus speeds.

These different types of RAM come in varying ‘form factors’, or packaging styles; that is, the physical size, number of pins, and so forth varies from one type to another. They also differ in voltage ratings and capacity.

Thus, different kinds of RAM cannot be mixed and matched. In fact, the motherboard is generally built to support only one type of memory, and different kinds of RAM will not even fit in the same sockets. In most cases, you can’t even mix modules with different capacities, although Intel does have a chipset for DDR2 that allows for mixing of different module sizes.

So before you replace or upgrade the RAM in your computer, you need to determine what type, speed, and the maximum capacity your motherboard can support. There are a couple of different ways to make this determination:

  1. Look up the information in the manual for the motherboard, which should be included in the documentation you received with your computer.
  2. Many manufacturers provide system and motherboard information online. Check out the manufacturer’s website.

Bear in mind that if you simply pull out your RAM and take it in to a local vendor to match it, you’ll likely get memory modules that will physically fit in your system, but will not necessarily have the same voltage and speed specifications.

There are a few other issues you’ll need to consider before buying RAM. First, you need to determine if there are any open memory sockets on the motherboard. If the sockets are ‘fully populated’, you’ll have to replace your current RAM with higher capacity modules and it might be more cost effective to purchase one large-capacity module than, for example, two smaller ones.

When adding RAM, you also need to match the metal type of the RAM module with that of the memory socket on the motherboard. There are two types available: tin and gold.

Over time, direct contact between two dissimilar metals can cause an oxidizing chemical reaction, so you must make sure that you use gold memory modules in gold sockets and tin modules in tin sockets. Because most modern computers use gold contacts, it’s not as much of a problem as it once was, but worth being aware of nonetheless.

In sum, the key to a successful memory upgrade is to be properly prepared with the information we’ve covered here. And, before we get into the upgrade procedure please review a few precautionary notes:

Precautions:

1. If your computer is currently under warranty, removing the cover of your computer may void that warranty. Double-check the provisions of your warranty. Sometimes just a call to the support personnel to discuss the issue is all that is needed to avoid such problems; if they are ‘directing’ your activities, your warranty should be safeguarded.

2. New RAM modules will be packaged in anti-static bags. Leave them there until you’re ready to install them.

3. Implement ESD safety procedures (avoid working on a carpeted floor or surface, be sure to wear your ESD wrist strap, and so forth).

4. In order to access the memory sockets on your motherboard, you may have to remove other components to gain clear access. For example, you may have to disconnect an IDE ribbon cable, or remove an expansion card. If this is necessary, be sure to label anything that you remove so you can reinstall it properly later on.

5. Removing an expansion card (such as a video card, sound card, etc.), is very straightforward. The circuit board is socketed onto the motherboard, and there is usually a retaining screw securing the card to the back of the case. The retaining screw serves to prevent the card from vibrating out of position.

First remove the screw. Then carefully wiggle the card out, exerting even force on the front and rear of the card. Don’t wiggle the card side to side, as this can cause the card to crack, or even worse, can cause the socket on the motherboard to break. Store the card in an antistatic bag while it’s out of the machine.

Memory Upgrade Procedure:

  1. Purchase the amount of RAM needed for your upgrade, using the guidelines we’ve discussed to ensure compatibility.
  2. Shut down and unplug the computer.
  3. Remove all peripheral devices from the computer, such as mouse, keyboard, monitor, printer, etc.
  4. Remove the cover from the computer.
  5. Ground yourself to an unpainted surface of the computer chassis with your antistatic wrist bracelet.
  6. If necessary, remove and label any internal components so as to give yourself unobstructed access to the RAM sockets.
  7. Remove the existing DIMM RAM modules by carefully depressing the retaining clips on each end of the module. Use even force on both sides, and do it slowly so the module doesn’t pop right out and up into the air. Set the old modules aside, storing them in an antistatic bag.
  8. Remove the new module from its protective bag, making sure to handle the module by the edges. Avoid touching the gold contacts, as the oil on your fingers can degrade the connection.
  9. Notice that the RAM module is ‘keyed’ – that is, there are notches spaced at different intervals to ensure that the module, when inserted, is oriented properly. Align the notches on the module with the socket on the motherboard.
  10. Make sure that the retaining clips are pushed back out of the way. Then seat the memory module into the socket by using your thumbs to press down firmly and evenly on both ends of the module. As you press the module into place, the locking clips will automatically rise into place and secure the ends of the module. You shouldn’t try to manually position the locking clips. If you’ve seated the RAM module properly and completely, the clips will move into proper position automatically.
  11. Replace any components previously removed.
  12. Leave the cover off temporarily while you do a quick check. Reconnect keyboard, mouse, and monitor, and power up the computer.
  13. Check the amount of RAM now installed (using the procedure previously described, which is slightly different for Windows XP and Windows Vista). If the amount of installed RAM shown does not match the capacity of the newly installed RAM, it most likely means that the module(s) simply needs to be reseated (power off, reseat, power on).
  14. Turn off the computer, replace the cover, and reconnect any remaining peripheral devices (printer, scanner, etc.).

Remember, replacing RAM is quite easy – as long as you’ve done the preparatory work properly and thoroughly. Congratulate yourself on a job well done!