cause a wide range of problems on a PC or a network. At minimum, all of the data in
RAM is usually lost, but depending on the applications or utilities running on the PC,
much worse could happen. For example, if you are in the middle of flashing the BIOS on
a PC when the power fails, the PC must be recovered through the boot block and the
BIOS flashing operations repeated. In the interim, the PC is not usable. Or, if the PC is
performing a defrag operation, updating the file system tables, or any other system
maintenance activity, the PC may be compromised.
Blackouts are caused by electrical storms; car accidents involving utility poles; the
electrical utility company being unable to meet user demands, such as the recent prob-
lemsinCaliforniawhentheyusedrollingblackoutstotrytosatisfyuserdemands;orato-
tal collapse of the power system due to user overload.
Typically, a blackout doesn’t just happen, and a series of surges and spikes occurs
both before the crash and when the power is restored. The damage to a PC happens not
from the power failing, but from the power surge on the power supply system when the
power is restored.Protecting Against Power Problems
There are several devices you can use to protect your PC and its peripheral devices. This is
one PC area where you get what you pay for, so how much protection you get depends on
how much you have to spend. At the low end are plug strips that include a fuse, and on the
extremely high end are standby generator and line conditioners. Most people protect indi-
vidual PCs with products toward the lower end of this scale, and enterprise networks and
Internet service providers (ISPs) tend to implement power equipment at the higher end.
The power protection equipment used for a home or small office system doesn’t need
to be very sophisticated or costly to provide the level of protection required for most situ-
ations. Depending on a number of factors, such as the quality of the electrical service
available and how often it fails, most home PCs can usually get by with surge protection
or a small uninterruptible power supply (UPS). More on the UPS later in this chapter. The
following sections look at each of the options available to a home or small office user.No Power Protection
While certainly not the wisest option, using no power protection equipment is definitely the
least expensive way to go, at least in the short term. However, power protection equipment
must be viewed as an insurance policy against the almost certain power-related problems on
your PC. The cost of the lowest-end protection is usually less than $20, which is a small price
to pay to protect your investment in your PC, printer, and other peripheral devices.
If you do choose to not use power protection equipment, at least use common sense
with the electrical cords.Nevercut off the grounding pin on a three-prong plug on the
PC’s power cord to plug the PC into a two-hole outlet. This removes the earth ground cir-
cuit from the PC, which is dangerous to both the PC and you and can cause electrical
problems all around.Chapter 23: Electrical Power Issues^603