2nd hard disk upgrade - symptoms and causes

[Peter Schmidt]

Hi y'all-

I just completed an exhausting 4 days (nights, actually) doing my ICUS 2nd
hard disk/P5.1 upgrade, and in the process managed to cause myself major
amounts of grief. (Please note that this is no way a reflection on Gil and
Lenny - it was me that was broken, not their instructions, which I think are
outstanding.)  Herein are a few of the worst gotchas I experienced and their
solutions.  If you're a real hardware type or have no plans to do the ICUS
upgrade, you should probably punt now...

The symptoms and causes listed below are the ones I encountered myself.  The
Cause lines refer to what caused the problem for me.  Bear in mind that the
same symptom may well have several different causes.  

Symptom: When I try to boot my UPC, the floppy light comes on immediately and
	I can hear the hard disk re-cal-ing over and over.
Cause: Your disk controller chip may be loose.  
Solution: Push it back down into its socket (back near the floppy-disk cable) 
	- firmly this time (not like when you installed the silly WD2010...).

Symptom: My upgrade seems to almost work.  I can talk to both drives, but I
	can't boot off them due to read errors.
Cause: Your cable from the motherboard socket to the extension board is too 
	long.  (Kudos to Gil for figuring this out at long distance.)
Solution: Shorten the cable - it should probably not be longer than about 6".

Symptom: My upgrade works until I try to close the case.  Then the motherboard
	goes back to being recognized as P3...P5.
Cause: The little metal flange that descends about a 1/4" below the back of
	the floppy drive is crushing the connector plugged into the 
	motherboard socket.
Solution:  Construct a lower profile connector, or remove the part of the 
	flange that is crushing the connector (the leftmost 1.5" looking from
	the front of the machine).  N.B. be very wary of sawing or drilling
	out the flange, as both methods will produce a lot of fine metal dust.
	I actually used a big pair of pliers and removed it bit-by-bit via
	metal-fatigue.  (Ugly, but it worked.)

Symptom: At boot, the hard and floppy disk access lights come on solid, but
	all I get is the little "dancing squares" at the top of my monitor.
Cause: One or both of the Vcc or GND connections to the motherboard from the
	extender board has come loose.
Solution: Remove cable, use continuity tester to find break, and fix it.

Symptom: I can boot with the upgrade installed, but my boot disk does a lot of
	re-cal-ing.
Cause: GND and/or Vcc on the motherboard socket are poorly connected (making
	loose contact) or are tied to an "empty pin" on the socket (e.g. due
	to bad soldering).
Solution: Reconnect, or clip extraneous pins (those not in the instructions,
	if any) so that they no longer are inserted into the motherboard 
	socket.

Symptom: I just fixed my broken GND and Vcc connections, and now my diagnostic
	floppy won't boot.
Cause: Something about that constant-access-light-on state has trashed the
	loader on your floppy.
Solution: Use backup diagnostics floppy (note no smiley).

Those were the baddies - hope this is helpful.

Regards,

Peter