Help! Bad motherboard RAM on 3B1...

[Steve Barber]

Well, last night was bad news.  A lightning storm was coming
into the area so I shut down shade, my 3b1.  Since I knew
his insides hadn't been cleaned in a while, and I had a battery
sitting around waiting to be installed the next time I had
the time and the opportunity, I pulled him all apart, cleaned
the (literally) mounds of cat fur and dust off the motherboard
and power supply, and replaced the battery with a coin-type
battery holder.  (With battery, of course!)

The humidity was high, so I wasn't too worried about static.

Well, looks like I got bit anyway.  On power up, I got the screen
full of bit patterns, then a clear screen for a split second, then
a screen of alternating all on/all off words, where it hung.

(i.e.:   xxxxx     xxxxx     xxxxx     xxxxx
              xxxxx     xxxxx     xxxxx     xxxxx
	xxxxx     xxxxx      xxxxx     xxxxx
	(etc.)
)

The LED pattern was:	Red:	ON
			Green:	off
			Yellow:	ON
			Red:	off
which a friend with the reference manual tells me is the code for
bad motherboard memory.

Now, I have 2Mb of motherboard memory, and I'm almost positive it
is not socketed.  I have a couple of spare 41256 RAM chips, but
desoldering all those chips does not thrill me, and even then I
have no idea which chip is bad.  (If I *were* to go and pull all
those chips, I'd most definitely stuff sockets in there...)

My friend suggested that AT&T had some diagnostic EPROMs that
would locate the bad chip.  I seem to recall that people on the
net had not been able to find these EPROMs in the past though.
Then I thought I'd write and burn my own diag eproms to find
the bad chip, until I realized that I had lost my assembler and
linker setup for the EPROM programmer when I lost shade.

So.  Does anybody have any suggestions?  I *have* to get this
fixed, and cheaply.  (I'm a student who needs a working computer
next fall, but can't afford to go back to school if I spend
much money getting this fixed!)

Those of you with worthwhile suggestions, please send e-mail to me
at:  barber at applga.aa.cad.slb.com.  I'll try to monitor these
groups from work, but I might miss something, so e-mail is best.

Thanks a million,
Steve
-- 
Steve Barber, Schlumberger CAD/CAM, Ann Arbor, Michigan
Work:   barber at applga.aa.cad.slb.com     (313) 995-6000
Home:   steveb at shade.ann-arbor.mi.us     (313) 665-0884