If changes to the BIOS solve the problem, this is a good-news, bad-news situa-
tion. The good news is that the display is now usable. The bad news is that
somethingcaused the BIOS settings to corrupt or change without your intent.
Possible causes include
A virus.Make sure your antivirus program is active and updated. If
you receive a warning of infection, be sure to follow all instructions
to remove the virus. After the virus is removed and the system fully
scanned, you should assign the BIOS to default settings or carefully
make choices of your own.
A failing backup battery or capacitor.Most laptops include either a
tiny replaceable battery or a capacitor that draws power from the main
battery when needed; these power sources keep alive the BIOS settings.
Check the instruction manual for your laptop for information on locating
this small coin-sized battery (if your computer uses one) and replace it
if necessary. One clue to a failing backup battery is an occasional or reg-
ular loss of date and time when the laptop is turned off for a few days.
Some laptops use a form of static memory to hold BIOS settings; this
specialized memory doesn’t require electrical power to keep recorded
information.If you must replace the battery, check the BIOS settings. It may be neces-
sary to assign the BIOS to default selections or carefully make choices of
your own.Exposure to a strong magnetic field.Magnetism can be generated by
metal detectors at security checkpoints, from medical equipment, and
other electronic devices including large monitors, television sets, and
audio speakers that are not electrically insulated (shielded) against leak-
age of electrical fields. Check the BIOS settings and go back to defaults
or manually make selections.
A problem with the BIOS itself.Within most modern laptops, the instruc-
tions that make up the BIOS are held in a specialized form of memory
called an EPROM — an electrically programmable read-only memory. This
form of static memory happily holds code for years, but can also be repro-
grammed to refresh the BIOS or to update it with a new version that adds
features to your laptop, supporting new elements of advanced operating
systems or hardware.Consult with your laptop maker for information about available BIOS
updates and instructions on how to download them. In most situations,
you download an executable file to your laptop over the Internet and
then click it to initiate an automatic installation.Chapter 3: Things That Go Bump In the Night (or Day) 45