First, solution starts with collecting facts. "Best
evidence" is the dead bodies. What is wrong with each disk -
the details?
Disk drive is composed of a disk drive computer and a disk
platter (including motor control electronics). Does disk
platter spin? What does disk drive computer do (sounds?) to
disk heads on powered up? Can motherboard computer talk to
disk drive computer? Use, for example, booting from a DOS
diskette and execute programs such as IDEINFO, INDENTIFY,
4DRVUTIL, or DUG_IDE. They ask disk computer computer for
manufacturer name, serial number, etc. Information should be
obtained from each disk when installed alone as the master.
If using disk as a slave, then use DOS or Windows to see what
FDISK reports. Also every (responsible) computer component
manufacturer provides diagnostic - for free. What do those
diagnostics report for each drive.
Second, power supply must contain essential functions so
that DC voltages cannot damage disk drive. Power line
protectors do nothing useful here. But many power supplies
are marketed to bean counter types - are missing essential
functions. A power supply retail price should be at least $60
AND manufacturer should provide a long list of numerical
specs. Essential in that spec list is Overvoltage Protection
(OVP). No OVP in combination with another supply problem
could 'surge' damage the disk drive. Again, no plug-in
protector will accomplish anything useful.
Of course, numbers from a 3.5 digit multimeter (definitely
not from motherboard monitor) are important. In this case,
best way is to measure voltage from each colored wire to black
wire using same cable that was previously used. Best place to
measure is where power connector is soldered to disk drive
computer board. Specific numbers are important information
and should be posted.
Intermittent black wires can also cause disk drive computer
board damage. Solid connection from black wire to disk drive
is more important than any other wire connection. Inspect
wire connection integrity.
Third, if a workroom does not have sufficient humidity, then
static electricity exists; no matter what you may think or
feel. Static electricity can damage or overstress (fails day
or months later) a disk drive. Work is best accomplished with
human electrically connected to computer chassis via a wrist
strap (that also includes a resistor for human safety). Never
remove or install components with computer connected to AC
mains. Some foolishly think that will eliminate static
electric damage. Wrong, very wrong.
With so many dead bodies, a pattern should be obvious. That
means numbers from power supply voltages. Does power supply
contain essential functions? Is motherboard ground connected
to chassis ground? Reports from manufacturer diagnostic and
from IDEINFO, IDENTIFY, etc also useful information. Are disk
platters are spinning and what happens inside drive on initial
powerup?
