Hardware Reference
In-Depth Information
example, when the processor is operating in backward-compatible real mode, only 1MB of memory
is supported.
See the
Chapter 3
section, “
Processor Modes
,”
p.
44
.
Note that even though modern 64-bit processors can technically address up to 1TB, modern
motherboards or chipsets generally limit the maximum amount of RAM to 8GB, 16GB, or 24GB. The
type of software also has an effect. The 32-bit versions of Windows (XP and newer) limit memory
support to 4GB (with only about 3.5GB usable by programs), whereas the 64-bit versions limit
support to 8GB, 16GB, or 192GB, depending on the edition.
If you run Windows XP, you should specify a
minimum
of 256MB, and preferably 512MB to 1GB or
more depending on the applications you intend to run. If you run 32-bit Windows 7 or Vista, the
absolute minimum
should be 512MB according to Microsoft, but I recommend a minimum of 1GB,
with 2GB to 3GB preferred. 64-bit versions of Windows 7 and Windows 8 have a 2GB minimum, but
perform better with 4GB or more of memory.
Beyond having the minimum to run the OS you choose, the way you use your system, especially the
applications you run, can be the major determining factor as to just how much memory is best. For
example, if you are a power user with four or more displays simultaneously connected to your system,
each with multiple open applications, or you run memory-intensive applications such as photo- and
video-editing programs, or if you use a virtual machine manager (VMM) like Virtual PC or VMware
to run multiple OSs simultaneously (each of those with open applications), you might want as much
memory as you can possibly install. Many older laptops won't accept as much memory as you might
want (or need) to install, so if you upgrade an older system that uses an obsolete (and expensive) type
of memory, the best tip might be to consider moving up to a newer system that can accept more
memory of a mainstream type that is less expensive.
When purchasing a new system, try to get it with all the memory you need right away. Some
motherboards are more limited in the number of memory sockets they contain, and some of those will
already be filled when the system is delivered. This means you might need to remove some of the
existing memory to add more, which makes future upgrades more expensive. The only caveat here is
that I often find that I can purchase memory much more inexpensively from third-party vendors than
from the system manufacturer. When purchasing a new system, check on how much the manufacturer
charges for the amount of memory you want, as opposed to taking the system with the default minimum
and immediately adding the desired memory yourself, purchased from a third-party memory vendor.
The following sections discuss adding memory, including selecting memory chips, installing memory
chips, and testing the installation.
Upgrade Options and Strategies
Adding memory can be an inexpensive solution; the cost of mainstream memory is extremely low
relative to other system components, and adding more memory can give your computer's performance
a big boost.
How do you add memory to your PC? You have two options, listed in order of convenience and cost:
• Adding memory in vacant slots on your motherboard
• Replacing your current motherboard's memory with higher-capacity memory
