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From: anderson@uwmacc.UUCP (Jess Anderson)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Zenith 158 Ram Upgrade
Message-ID: <883@uwmacc.UUCP>
Date: Thu, 15-Jan-87 08:54:09 EST
Article-I.D.: uwmacc.883
Posted: Thu Jan 15 08:54:09 1987
Date-Received: Fri, 16-Jan-87 00:42:41 EST
References: <314@rocky2.UUCP>
Organization: UWisconsin-Madison Academic Comp Center
Lines: 34
Summary: 150 ns chips are fine.

In article <314@rocky2.UUCP>, reintom@rocky2.UUCP (Tom Reingold) writes:
> In article <1294@ncr-sd.UUCP>, lodman@ncr-sd.UUCP (Mike Lodman) writes:
> > Would someone please respond via e-mail and tell me what ram chips
> > are needed to upgrade a 256K Zenith 158 PC to the full 640K?

> I believe you should get chips with a rating of
> 120ns to ensure proper operation at 8 MHz.  

I have done this. I used 150ns chips (Toshiba, but any maker with
a good rep and a favorable price should be OK). We have a PC maintenance
guru where I work, and he said I would have no problems with 150 ns chips
and need not invest in faster ones. I have been running the machine at
8 MHz since September with a full load of RAM. I have no problems of any
kind (knock wood). There is a simple tool that compresses the pins slightly
to make inserting the chips easier on your nerves. I didn't know about
this tool at the time, but I had no problems with installation. 

If you end up wanting more RAM for RAMdisks, I've heard that not all
add-ins work. For example, Tall Trees JRAM does not work. AST RAMpage
does and Intel AboveBoard does. I have not yet tried either.

On other upgrade matters, I have added an ST238 with Adaptec 2070a
controller to get a 30 MB hard disk (works like a champ!).

If you want an EGA, be aware that not all EGA boards work in a Z-158,
but here I don't have any other reliable information. Doubtless
someone else does. Good luck and have fun -- I sure am having fun
with my machine!

-- 
==ARPA:==============anderson@unix.macc.wisc.edu===Jess Anderson======
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