Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!clyde.concordia.ca!usenet
From: usenet@clyde.concordia.ca (USENET News System)
Newsgroups: comp.sys.ibm.pc
Subject: Original IBM PC -- Don't laugh!
Summary: How to upgrade memory?
Keywords: RAM chips / 64kx1 / 4164
Message-ID: <1747@clyde.concordia.ca>
Date: 19 Dec 89 16:02:16 GMT
Reply-To: smw@maxwell.Concordia.CA ( Steven Winikoff )
Organization: Concordia University, Montreal, Quebec
Lines: 49

From: smw@maxwell.Concordia.CA ( Steven Winikoff )
Path: maxwell!smw

It seems funny in these days of 486's even to consider the original 64k
PC (not XT, PC!)...   But a friend just paid $100 for a prehistoric PC
and a (real!) Epson printer!

Now, of course, he wants to upgrade...

This machine has a memory board with 27 of its 36 sockets populated.
The chips are labelled as follows:

	TMS 4164 - 15NLJ
	GAV  8410 10

(Actually that might be 6AV instead of GAV; it's difficult to read.)

From the fact that this provides 128k in additional memory, I conclude
that these are 64k x 1, 150 nanosecond parts.

Questions:

  1)  Am I right?

  2)  If so, then this board will only hold another 64k worth of these
      chips.  Can I replace them with larger chips?  Who does the 
      address decoding -- ie will he need a different add-in board?

  3)  In general, what would you do in this situation?  


Also, I would normally recommend replacing the 8088 with a V20, but
I really don't know if this system can handle one.  Does anyone still
sell V20's at 4.77 MHz???

One last point.  The operations manual that came with this machine is
missing the pages which describe the switches on the motherboard... so
even if I knew what to add, I still wouldn't know how to indicate to
the system that it had additional memory!

Can anyone help???


Thanks in advance!
------------------------------------------------------------------------
Steven Winikoff                                 smw@maxwell.concordia.ca
Software Analyst
Concordia University Computer Centre            voice: (514) 848-7619
Montreal, Quebec, Canada                               (10:00-18:00 EST)