A thought...

[Robert Harris]

The +/-dc on the mother board is low power.  Off the mother board, no
-12vdc is needed.   The drive connectors only need +12vdc and 5 vdc.
The 5 vdc requirement can get very hefty as thats what runs most of the
stuff or is regulated down to 3.x volts.

The battery can be regulated to produce 12vdc so not a biggy,
Producing the 5 is going to need most of the power.  The -12v
is mainly bias.

On same topic, make sure mother board is late model GREEN mother
board with power saving logic and BIOS or its a tosser for automotive 
use.

Also, toss the concept of expensive industrial disk drives for booting.
Use a CD-ROM.   The CD recorder is only about 700 bucks and if 
you ain't ran them off one of your computer nerd friends probably 
has one.  A CDR disk only costs about 7 bucks, is impervious to even
grease monkey hands and won't break before your bones are mush.

Use a cheap ass 3.5 floppy to boot, load from the cheap 4x CD ROM with
the cdr disk in it, and write back critical tables to the floppy.  Floppy
should
last at least a month, and a 25 cents apiece, toss it every two weeks to be
super safe.  Use a cheap tape drive - 250 meggers available for under a 
hundred bucks to record data logging, and maybe even writing back critical
tables.  Since you are using a GREEN motherboard, you never turn the 
PC off.   Then when you turn key, you just generate interrupt, kick out of 
green mode and be styling.

If you aint got a nerd friend, use the money you just saved from thinking 
about industrial strength hard drives, and buy the CDR yourself. Works
great for pirating --- OOOPS - backing up CD ROM software.

Also, forget old MFM RLL ESDI hard drives. Day be doggie doodoo and 
are not made anymore.  The early ones take more power to run than a 
complete Pentium 166 system with everything on it.  BTW, they are built
like a tank outside and the heads and platters are just as fragile as the 
new stuff.  But if you really want one, you can generally find one at the 
bottom of the junk bin or dumpster of your local PC shop - no economic
value.

The only thing that sucks more than politics is the politicians.
Robert Harris <bob at bobthecomputerguy.com>


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