• Please review our updated Terms and Rules here

Bought an Old Zenith 386 that I remember having as a kid and...

thegenerallee86

Experienced Member
Joined
Feb 1, 2021
Messages
143
Or at least pretty close to it anyways and need help figuring out what one I actually have and I know it is a 386 just not sure which one it is the one with 4 bays on the front and this is the Model number on the back: ZBF-3339-EK ? I would like some help figuring out exactly what it is and what 386 it has? Please and Thank You.
 
I've been scouring the net looking for anything related and have found nothing. You need to get the model number off the motherboard and see if you can find it listed in Total Hardware here:

https://arvutimuuseum.ee/th99/m/m386_5.htm


It may be this one:

https://arvutimuuseum.ee/th99/m/U-Z/32409.htm

or it might be this one, not sure though:

https://arvutimuuseum.ee/th99/m/U-Z/32393.htm

I got some pics here:https://drive.google.com/drive/folders/13QfLSl84cH5PtEhCSYmcUJiiywv4v5p7?usp=sharing and looks like it's a 16Mhz with 16Mhz coprocessor and everything is in expansion slots and very little is on the actual board. All I could find for numbers on the board were 85-3333-01, 03287 and then to the side of that a 31 B it was just where I couldn't get a pic of it.
 
There's something wrong with the pics you uploaded. When trying to view get "no preview available". When I download and try to view Windows says they are an unsupported type?

Edit: They are working now?
 
Last edited:
There's something wrong with the pics you uploaded. When trying to view get "no preview available". When I download and try to view Windows says they are an unsupported type?

Edit: They are working now?
Try this one hopefully
https://drive.google.com/drive/folde...p7?usp=sharing


No.

The 33Mhz model has the CPU and memory modules on the main board.

The 16Mhz machines have a backplane with separate CPU and Memory boards.

BTW, the cases for both machines look very similar.

Just curious why you couldn't take out the 16mhz on the card and put in the 33Mhz 386?
 
Last edited:
Try this one hopefully
https://drive.google.com/drive/folde...p7?usp=sharing




Just curious why you couldn't take out the 16mhz on the card and put in the 33Mhz 386?

The clock speed would need to be adjustable to meet the 33MHz speed (usually through jumpers or dip switches). If you plug in a 33MHz CPU it will more than likely just run at 16MHz any way. You also have an NPU. If you do find a way to upgrade to a faster processor you'll also need to get a matching NPU.
 
The clock speed would need to be adjustable to meet the 33MHz speed (usually through jumpers or dip switches). If you plug in a 33MHz CPU it will more than likely just run at 16MHz any way. You also have an NPU. If you do find a way to upgrade to a faster processor you'll also need to get a matching NPU.

I see a bunch of jumpers and switches but there is nothing saying how to set them or what they do exactly on the card and here are some new pics I took of the card:
https://drive.google.com/file/d/14jn...ew?usp=sharing,
https://drive.google.com/file/d/14vC...ew?usp=sharing,
https://drive.google.com/file/d/14vr...ew?usp=sharing,
https://drive.google.com/file/d/150q...ew?usp=sharing,
https://drive.google.com/file/d/159h...ew?usp=sharing,
https://drive.google.com/file/d/15CY...ew?usp=sharing

I did find this but not sure if it is right or not: Z-3300 SERIES Motherboard Settings and Configuration (stason.org)
 
Last edited:
Nothing there about setting CPU speed, just NPU speed for High/Low. I highly doubt you're gong to be able to upgrade this computer beyond the 16MHz it's already set to. This was one of the first 386 computers available at the time. The idea of 33MHz was probably still a few years off.
 
Nothing there about setting CPU speed, just NPU speed for High/Low. I highly doubt you're gong to be able to upgrade this computer beyond the 16MHz it's already set to. This was one of the first 386 computers available at the time. The idea of 33MHz was probably still a few years off.

Yeah I had a feeling about that Oh well now want to figure out what I can do with it and what old Games and Operating systems I could play and use on it I was going to try for OS's like DOS, Windows 1.0 to 3.11 at Most, Cause I already have a IBM PC series 350 P75 75Mhz Pentium for 486 Games up to early Win 95 Games!
 
Yeah I had a feeling about that Oh well now want to figure out what I can do with it and what old Games and Operating systems I could play and use on it I was going to try for OS's like DOS, Windows 1.0 to 3.11 at Most, Cause I already have a IBM PC series 350 P75 75Mhz Pentium for 486 Games up to early Win 95 Games!

When I had mine, I was in Computer Science Curriculum at University of North Florida. I was running OS/2 2.1 and Borland Turbo C. Then went to IBM CSet++ compiler.
 
FWIW

Check out the cost of a 4MB memory card for this machine P/N Z-515

https://www.pestingers.net/pages-im...computer-history/cat-history/1987/h386-87.jpg.

Pretty expensive

When I had mine, I was in Computer Science Curriculum at University of North Florida. I was running OS/2 2.1 and Borland Turbo C. Then went to IBM CSet++ compiler.

I only ever used the original one I had for word processing and it was my very first PC computer that I got from my uncle which I don't know where he got it from.
 
If you do find a way to upgrade to a faster processor you'll also need to get a matching NPU.

Entirely depends on the machine architecture. The 387 was designed to be able to run asynchronously from the 386, and many systems did this to have a slower 387 or even 287 installed. If the machine in question was a very early 386, the "High/Low" jumper may be to use a 287 at a slower speed.
 
Back
Top