[comp.sys.amiga.tech] What's the latest on A1000 expansion flakeyness

karsh@trifolium.SGI.COM (Bruce Karsh) (05/10/89)

I recently added an Expansion Technologies 48mb disk drive and a Spirit
.5Mb memory expansion to my Amiga 1000.  I wound up with a case of the
Amiga 1000 expansion flakies!

The system would boot about 50% of the time and hang after a command or
two.  The rest of the time it wouldn't boot at all.  Sometimes it would
just hang, sometimes I'd get a blue screen, and sometimes I'd get a
kickstart hand.

So I installed the ground wire connecting the 4 PALs to the motherboard
ground.  I used a single piece of heavy gauge of wire which I soldered
to each of the 4 ground pins (pin 10) on the pals at J, K, L & N.  I
fired up the system and was pleased to see that all was well.

Well, almost all was well!  Now my machine crashes about every 15-20
minutes.  The symptoms are either the thing goes dead, i.e. it won't
respond to input at all.  Or I get a blue screen followed shortly by a
kickstart hand.  In both cases, I have to re-kickstart the machine.

Besides the PAL ground wire, here are some other proposed fixes I've
heard of:

     *  Attach a separate ground wire from the 68000 processor's ground
	pin
	to the motherboard ground.

     *  Replace the 68000 processor chip with a Motorola 68000 chip.

     *  Replace the plastic 68000 processor chip with  a ceramic 68000
	chip.

     *  Replace the PAL chips with ones manufactured by MMI.

So, here are my questions:

     *  Are there any other proposed fixes which I should be aware of?

     *  Which proposed fixes work and which are witchcraft?

     *  What is Commodore Amiga's official position about the Amiga
	1000 expansion flakies?  Do they acknowledge its widespread
	occurence?  Do they have a detailed understanding or
	explanation of what is occuring.  Do they have any service
	bulletins or repair recommendations about this problem?  What
	do they expect their Amiga 1000 owners to do?
--

			Bruce Karsh
			karsh@sgi.com

In fact men will fight for a superstition quite as quickly as for a living
truth - often more so, since a superstition is so intangible you cannot get
at it to refute it, but truth is a point of view, and so is changeable.

u555917504ea@minnie.ucdavis.edu (0040;0000008360;0;340;141;) (05/10/89)

In article <32426@sgi.SGI.COM> karsh@trifolium.UUCP (Bruce Karsh) writes:
>I recently added an Expansion Technologies 48mb disk drive and a Spirit
>.5Mb memory expansion to my Amiga 1000.  I wound up with a case of the
>Amiga 1000 expansion flakies!

...

>
>     *  Attach a separate ground wire from the 68000 processor's ground
>	pin
>	to the motherboard ground.

	I myself have .5 megs on a spirit board, with a Cltd SCSI.
I had the EXACT (and I mean exact) same problem. After hooking up the
68000 ground, the computer worked fine. (Only crashes every few days
now...)
	Good Luck!

	-Bruce Rogers
	currently u555917504ea@minnie.ucdavis.edu

_______________________________________________________________________________
Just a man whose circumstances went beyond his control....