DEFMTH2.CVP   911215
 
                        Hardware damage
 
The myth of viral programs damaging hardware seems to be one of
the more enduring.  *No viral program yet found has been
designed to damage hardware, and THERE HAS NEVER BEEN ANY
CONFIRMED CASE OF A VIRAL PROGRAM DIRECTLY CAUSING PHYSICAL
DAMAGE TO COMPUTER HARDWARE.*  Is that plain enough?
 
It *is* possible for certain pieces of hardware to be damaged by
software or programming.  To the best knowledge of the
international virus research community, no such programming
(with the exception of low level formatting, see below) has ever
been found on an existing virus "in the wild."
 
Monitors - certain older types of monitors (notably early IBM
mono graphics adapters) could be made to "freeze" the sweep of
the electron beam, and thus "burn in" a section of the screen
phosphors.  No one has ever burned a hole in a monitor, nor have
they ever caused one to overheat and "blow up" with software.
 
Power supplies - cannot be addressed by software.  No one has
ever "melted down" a power supply with software.
 
Printers - as with any physical device can be damaged by getting
them to do any one thing for too long.  This, of course, depends
upon the machine running unattended for a long time.
 
Drives - some drives can be damaged by "pushing" the heads
beyond normal limits.  On others, this is a good way to find
more disk space.  Certain drives can be damaged by having the
heads "seek" back and forth at a resonant frequency.  (Usually
older drives, for mainframes, are more susceptible to this. 
There is also a story, likely apocryphal, that one computer
company set up a "portable" computer, including banks of disk
drives, in a semi-trailer for demos.  The first time the truck
took a turn with all the drives running, it flipped over due to
the enormous stored angular momentum of the spinning platters.)
 
IDE controllers and drives do not allow for the normal calls to
low level format the drive.  If such a call is made, the results
are uncertain.  The drive will not be formatted, but it will not
be left in a usable state.  IDE drive manufacturers have not, in
the past, shipped programs for low level formatting, and so a
call for a low level format on an IDE drive has been, to the
normal user, no different than hardware damage.  As this has
become known in the user community, more IDE manufacturers have
been shipping the formatting programs.
 
Hardware damage by software is possible, but extremely rare.
 
copyright Robert M. Slade, 1991   DEFMTH2.CVP   911215

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