Xref: utzoo comp.sys.att:4951 unix-pc.general:1881
Path: utzoo!attcan!uunet!labrea!rutgers!att!ttrdc!ttrde!pfales
From: pfales@ttrde.UUCP (Peter Fales)
Newsgroups: comp.sys.att,unix-pc.general
Subject: Call for Help:  3B1 1MB to 2MB upgrade
Keywords: Any hardware gurus out there?
Message-ID: <803@ttrde.UUCP>
Date: 16 Dec 88 04:13:06 GMT
Organization: AT&T, Skokie, IL
Lines: 22

Here's one for you hardware experts.  I have been trying to upgrade my 3B1
from 1MB on the system board to 2MB.  I have a copy of the schematics and
I thought it would be fairly easy.  I have done the following.

	1) Installed 4 Motorala 74F258 Multiplexers
	2) Installed 36 Sockets, and 256KB DRAMS
	3) Installed 27 0.1 uF bypass capacitors 
	4) Installed 16 33 ohm resistors (rather than the resistors
		packs, the parts were backordered and I was impatient)

The system now boots and runs fine, but it doesn't recognize the extra
memory.  Is there anything more I have to do?  Assuming I have done 
all that is required, how can I go about testing the thing?  As far
as I can tell, the diagnostic disk can not test any memory not
recognized  at boot time.

As they say, thanks in advance,
-- 
Peter Fales			AT&T, Room 2F-217
				200 Park Plaza
UUCP:	...att!ttrde!pfales	Naperville, IL 60566
Domain: pfales@ttrde.att.com	work:	(312) 416-5357