[comp.sys.ibm.pc.hardware] Zenith Z-159 memory upgrade problem

ebrill@bronze.ucs.indiana.edu (Ed Brill) (07/27/90)

I have been trying for the last two months to upgrade the memory in my
Zenith Z-159 PC XT clone.  A coworker generously donated some 256k
chips to the cause, and I installed them without a problem.  The system
then reported 640K memory -- even though I had put 18 chips in, which should
bring the system up to 1024K, not 640 (I started with 512)..

Through some calls and some research, I found that the boys in Michigan
designed their system to require what they call "Control PAL" chips on the
board to allow the system to use memory beyond 1 Meg (640 usable).  The
catch here is that nobody stocks these chips because they are Zenith
proprietary...and ZENITH ONLY SELLS THEM AS PART OF AN EMS UPGRADE KIT,
which costs several hundred dollars.  They also told me that the 5 control
chips I need are $20...which I would spend.  But they won't sell me
the control chips without the EMS upgrade which includes 18 256k chips...
which I already got.

Has anyone else encountered this situation, and found a helpful source
of Control PAL chips?  I have more information, if it would help -- send
me email.
---
Ed Brill     (708) 719-7800       | My boss won't let me use my opinion on
Floral Network, a Division of FTD | the job...so USENET gets it instead!! :)
--------------------------------- |------------------------------------------
ebrill@ddsw1.mcs.com              | ebrill@bronze.ucs.indiana.edu

micki@thraine.UUCP (Michelle Stone) (07/28/90)

In article <52252@iuvax.cs.indiana.edu> ebrill@ddsw1.mcs.com (Ed Brill) writes:
>I have been trying for the last two months to upgrade the memory in my
>Zenith Z-159 PC XT clone.  A coworker generously donated some 256k

>Through some calls and some research, I found that the boys in Michigan
>designed their system to require what they call "Control PAL" chips on the
>board to allow the system to use memory beyond 1 Meg (640 usable).  The
>catch here is that nobody stocks these chips because they are Zenith
>proprietary...and ZENITH ONLY SELLS THEM AS PART OF AN EMS UPGRADE KIT,


Welcome to the wonderful world of Zenith Computers... I had a similar
problem with a machine that I purchased many years ago.  While disk
and memory prices plummeted, those for my machine upgrades remained
excessively high.... so I dumped the machine.  In any case, I would
suggest that you find your nearest HeathKit dealer and just go 
order the parts you need.  Yes, they sell Zenith stuff as kits and
you can always get replacement parts through them.  Good luck!