147. Nursing a sick computer
By Andrew D. Wright
What do you do when your computer starts shutting down suddenly on its
own? Some folks give it to the kids and buy a new one. If that's not you,
Sudden shutdowns can come from viruses, from memory errors, or from some
hardware cause such as overheating.
Rule out the virus first. There are a number of different antivirus
programs offering very good free versions. Download and install one if you
don't have one already running. Make sure it's updated with the newest
virus definitions before scanning your whole computer. Virus definitions
are usually updated daily.
If you already have an antivirus program running, check the date on its
definitions - if they are more than a day or two old, download new ones.
Don't trust antivirus products more than a year or so old.
Errors in memory can be caused by exploding stars, or more accurately by
the cosmic rays they produce. Constantly streaming through all of us all
the time, if a high energy particle hits the right spot on a stick of
computer memory, it can make the memory unusable.
To test memory, download Memtest 86+, a free utility. Burn the disk image
to a blank CD then boot the computer from the Memtest CD. The tests will
run automatically, writing and reading data to the different parts of your
memory. If it goes through the entire run with no errors, you can rule out
memory. If you find errors, replace the memory with a new stick.
If your computer is more than a couple of years old and particularly if
you've had it sitting on the floor all that time, lint and dust may have
built up inside it causing it to overheat. Computers don't take
overheating well; they can start acting in bizarre ways or just flat out
Dust can be blown out with canned air. Fan blades on processor coolers can
be cleaned - with the computer off - using dry cotton swabs. Twirl them on
both sides of each fan blade while holding the fan from spinning with your
finger. Don't blow fans with canned air since this can damage them by
spinning them too fast. Don't use a household vacuum cleaner to clean dust
out of a computer as this can create a damaging static electrical charge.
Another problem that can affect older computers is circuit fatigue from
being powered on and off. When on, the computer produces heat and
components expand. When turned off, these components cool and go back to
normal size. Over time this can loosen connections, which can be fixed by
simply re-seating the component. It can also loosen solder joints on
printed circuit boards, which can be more of a problem to fix.
Unexpected shutdowns can also come from sub-standard components.
Capacitors on the motherboard, the cylinder shaped things that look like
little grain silos, can rupture and leak their electrolytic fluid. This is
a particular problem with low cost computers made around 2002 and 2003. If
you see some dried crud bulging out of the top or bottom of the capacitor,
it's time for a new computer.
If the sudden shutdowns also come with the famous Blue Screen of Death,
where the screen is all blue except for some white text, then there is
probably some kind of software failure. Go to Windows Device Manager
(Start - right click on My Computer - Properties - Hardware - Device
Manager in Windows XP) and look for any yellow exclamation marks denoting
unhappy hardware and reinstall its drivers or download new drivers.
Memtest 86+ (free):
Mousepad #60 - Spring cleaning your computer:
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Originally published 30 January 2009