Saturday, February 12, 2011

Zenith Eazy Pc Teardown

Somewhere on the West Coast of Vancouver Island...

I played hookie from Free Geek this week and hung around Vancouver Island. Fortunately I saved up a teardown for just such an occasion.

This one is an ill-advised entry into the world of early home computing and I feel no regret in tearing it to pieces.

Pictured above is the Eazy PC, Zenith's valiant attempt to make the worst PC-compatible computer possible. (This one, the most expensive of the three models they offered, listed for $1699 US according to a very nasty review in September 1987's InfoWorld issue.)

The black-and-white screen and base are a one-piece unit, and the computer itself has almost no capability for expansion whatsoever. Here's the back:

That chunky cartridge is the so-called "Option Connector", where you could attach one of apparently only two custom-made upgrades to the machine. The one pictured here is a 128KB RAM module, extending the built-in 512KB RAM for a grand total of 640KB -- the maximum that this machine could take.

Slightly concealed behind the attached module are the printer (parallel) and mouse (serial-ish) ports. Apparently the mouse port isn't even a full-fledged serial port, but enough of one that a mouse would function.

The only other alternative to the pictured memory expansion is Zenith's memory/modem/serial port option, which included 128KB ram, a 1200 baud Hayes-compatible modem, and an additional serial port. Add another $399 USD.

These option bricks were attached with a ribbon cable:
A terrible, terrible idea
This might just be the worst kind of expansion ever invented. I assume Zenith's motivation for this was a sense that people were afraid of opening up computers and tinkering with the guts; fair enough. So why give them a ribbon cable? These are relatively easy to misalign and aren't at all meant to take a lot of wear and tear. The only answer I can think of is that Zenith was simply too cheap to do a proper job. Putting RAM on the end of a ribbon cable is like leaving your phone at the bottom of a stairwell and conducting a conversation by yelling at it. (Works just fine if you're Bonzo, I guess.)
Another look at a stupid, stupid idea

This model had a built-in 720KB 3.5" floppy drive and a whopping 20MB IDE hard drive. That's right: except for the 1200 baud modem and extra serial port (and of course the stock mouse and keyboard, long since separated from this unit), we're looking at a MAXED OUT Zenith Eazy PC with a list price of almost $1800 USD. And those are 1987 dollars -- today that would be about $3400 CAD.

The rest of the InfoWorld review (available on Google Books) is pretty amusing. Zenith, you blew it. The IBM PCjr sucked for many of the same reasons four years earlier, but at least it sucked for cheaper.

So, a look at its guts, for what it's worth.
Eazy PC, justifiably decapitated
The screen is permanently attached to the base; the screen also seems to contain the power supply for the whole unit, so two connectors come down into the main chassis from there: power, for the motherboard, and video data back up to the screen from the video controller.

(Incidentally: does anyone else remember when power switches used to be on the backs of screens? In this case, the power switch for the whole unit is on the back. I wonder what engineer first did this, thinking to himself "yes, this is where it belongs." Anonymous engineer, we wonder what you were thinking.)

The hard drive is on the upper left of the chassis in the picture below, and just below that is the 720KB floppy drive. The motherboard is underneath metal sheathing -- the only sign that any care at all was put into this design. I would've expected them to line the top of the case with tin foil. You can also see the little PC speaker square in the middle of the chassis. It's mounted on a little custom metal bracket -- a maneuver that screams "Oops, we forgot to find a place for this!"

Under the metal sheathing
Underneath the metal sheathing, you can see the motherboard on the left. This system uses an NEC V40 CPU, which was supposedly PC-compatible and ran at speeds somewhere between a PC and an AT. You can see the square CPU chip at the far left of the motherboard.

On top of the hard drive, there's a white adhesive sticker with a bunch of free space. This is where the manufacturer could document bad sectors on the hard drive -- they often shipped with known defects and the manufacturer would actually print a list of them and stick them to the drive.

Vadem IBM-compatible BIOS
Here's the BIOS chip -- I can't find much information on Vadem, but they appear to be a subcontractor that Zenith used to manufacture some of their computer-related equipment. I suspect most of the compatibility problems that the InfoWorld article described originated here.

Good riddance to this one. If I had a time machine, I'd go back to 1987 and warn the prospective buyer of this ill-facted bit of garbage to spend a little bit more and get one of these instead. (Compaq, why do I love your early portables so much?)

One saving grace for this silicon mistake -- it still boots after almost 25 years. Sort of.


  1. This is hilarious. And thanks for the Led Zepplin link -- I had no idea. I will be listening with new ears. So much cultural history to catch up on -- it never ends. I first learned to use a computer in 1988 when you had to go in from DOS, using DOS commands and then use WordPerfect I think it was. And then there was Word Star too. With floppy Floppy Discs. "Careful! Don't bend them!" our instructor said.

  2. Anna, I remember a lot of that stuff well -- I dove into computing with the perfection-of-a-dying-breed that was Wordperfect 5.1 on DOS, and used Word Star under CP/M on the infamous Osborne I. Rarely that kind of thing still comes into Free Geek and those are the days you'll find me weeping into the recycling bins at the back; we don't have a museum mandate (yet) so those machines often get (lovingly, painfully) scrapped.

    I don't know why they would call them "floppy disks" and then act surprised when you try to bend them...

  3. My first computer was one of these with 512KB of RAM and two floppy drives instead of a hard drive. My dad acquired it used from somewhere in 1989 and I finally retired it in 1997 or 98. It was still working flawlessly running some version of DOS and Word 4.0 and an assortment of other basic DOS programs and games but someone had given me a Mac Plus and a 40MB hard drive the size of a VCR to play with and I was running out of desk space. It wasn't a good computer but mine was reliable at least. I seem to remember having a dislike for that version of Word and using DOS Edit most of the time instead. I still dislike Word though... Thanks for the memory.

  4. Hey Fidler! I see you've relocated to China -- congrats, sounds interesting, but it's a shame you can't pop in to weep over all the old gear. Give me a heads-up if you're back in town and I'll give you a tour.

  5. Hey Alec!

    I didn't recognize you from your handle. I came in and volunteered a few times doing tear downs last spring before I left actually but I will definitely pop in to see what's changed next time I'm back for a visit.

    I donated a lot of old gear from my apartment when I left town including a brand new(ish) 1997 Toshiba Libretto 50, still in the box. I think it was only booted once the time I fired it up to see if it worked and still had the receipt for $1800 in the box. I paid $10 for it at a garage sale. That's some serious depreciation...

    Interesting little machine but not really useful I suspect because there was no easy way to get it on a network, no USB and the keyboard sucked. I was going to try to run Puppy Linux on it but with only 32MB of RAM, it might have been swapping too much to be practical assuming that that old Pentium could even handle it. It seemed to run Windows 95 OK for what that's worth. Anyway, I was hoping to see it go into the museum as an interesting artifact of laptop history but I suspect it went to the recycler instead :( So it goes.

  6. Those little machines are neat. We get a few of them -- or other sub-compacts like the early Sony Vaio sub-compact machines -- and sometimes they come in mint condition. It's a shame they're really not good for anything. The batteries are most often dead, and though there are a few distros that'll still run, it's pretty hard to convince anyone to invest time and effort when a cheap netbook runs a thousand times the speed...

    We don't have a museum, but a number of us would love to see one start. There just isn't enough space; we'd need a pretty hefty grant from someone (CoV?) to get started. It sure would be fun, and I know a lot of retro-junkies would come crawling out of the woodwork.

  7. My dad has one of these, including all the manuals, mouse, keyboard, printer, etc. and is interested in selling it. Do you know what it might be worth in good condition?

  8. Hey Robynowitz -- unfortunately a mint Eazy PC is worth only slightly more than zero. They're pretty close to unloveable. The best way to verify IMO is to check EBay's completed auctions listings. Practically speaking, your best bet is to find a tinkerer who either wants to use the chassis for something or has an unjustifiable nostalgia for this beast. Blow it out on Craigslist and if you make anything more than $20 on it, treat yourself to a sandwich.

  9. Yes, it was overpriced, but I bought mine ((in 1987) on sale (a floor demo) at a very low price and I saw it on sale in other places.

    Yes, it didn't have much memory, even with the clunky looking expansion (which I bought) but it was enough memory to run Wordperfect and PC-File. In fact since I ran Wordperfect and PC-File from one of the two floppies there was enough memory left for me to create a virtual C drive that ran at blazing speeds compared to real hard drives at the office and in the homes of friends and family. Of course I had to remember to always back it up before shutting off the computer. But there was a lot of floppy disk space to back into since it was one of the very rare computers using 3 inch floppies at the time and software developers were still planning for the limited capacity of 5 inch floppies.

    Yes, it had a "fixed" monitor but it could swivel in all orientations, and the fixed monitor meant that Zenith engineers used all their TV know-how to put in there one of the highest resolution, proprietary monochrome screens on the market. The resolution was outstanding compared to what I saw at the office or elsewhere. Also, they put the power supply in the monitor casing so that they could ventilate it without using fans. It was truly silent.

    Yes, the keyboard was limited in that it did not have things like n inverted T cursor control and a few other buttons , but it was a solid, well built keyboard with virtual clicks and superior to the flimsy things that were so current in clones back then.

    Yes, it could not be expanded but with that virtual drive it served me fast and well for long years. It was remarkably resistant. For all I know it might still be bootable.

  10. ndgmtlcd, you're right: it did what it promised, and for the most part it was solidly built. Ours powered up without complaint at the ripe old age of 25, failed hard drive notwithstanding. I'll never love it, but it ain't the worst computer ever built -- that prize goes (IMO) to the IBM PCJr. Maybe I'll write about that next.

  11. This couldn't be any funnier, and appropriate timing for me. I've been collecting some of my old computers, and the Zenith Eazy-PC was my first computer!

    Yeah, it wasn't great, but I had good memories on it. Played chess, got onto the US Videotel network on it with the awesome speed of 1200 baud, and did my college work on it. Bitter sweet times with a bitter sweet computer (meaning I could never quite get that thing to do everything I wanted). I always thought the mouse port was dead, but now that I read this, no wonder mice wouldn't work on the built-in serial port!

    I agree that it had the best keyboard I ever had (insofar as I can remember now) -- nice and soft to the touch, with a pseudo 'clicking' sound. I miss that keyboard. It also had a beautiful high-resolution monochrome screen. For some reason, I always thought it could be upgraded to color with one of those block-ish adapters on the back, but I guess not. Maybe the salesman lied about it?

    In any case, thanks for posting this. Too bad you destroyed a wonderful piece of history, even if infamous. :)

    If Robynowitz is still selling, give me a shout!

  12. Thanks, Mike -- believe me, it pains me to scrap this stuff but we don't have much of an alternative. We used to stockpile "museum-worthy" gear and it only ended up piling up in expensive storage space. I don't have the gumption to solve that problem on my own, so in the meantime my half-solution is to at least write up an elegy and take some photos before it hits the recycling bin.

    I dearly hope someone will approach us with a good plan for saving the gems. Some of the volunteers -- myself included -- end up taking some of it home. But as for Free Geek, it's too far out of our mandate.

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  14. Say MikeK,

    If you're interested, I have one of these machines myself. Found it in the dust bin a few years back.

    Unfortunately, the case and monitor bezel had gotten broken a bit, and the monitor popped off the base, but luckily the wires were all ok, so I pieced it back together and plugged it in.

    It booted up perfect! Played SimCity for DOS on it for a few hours off a 720kb floppy with a standard keyboard and mouse, worked great!

    You're right about the display now that you mention it, it is pretty sharp. Guess Zenith knew how to make CRTs!

    Is you're interested MikeK, I'd sell it to you for $20 + shipping. Let me know what you think.

    By the way AUTUIN, would you know the model number of the HDD in your EzPC? I have the dual floppy model, and was thinking of fitting a HDD in it, but I need to know whether the IDE bus was 8-bit or 16-bit. I could tell this from the HDD model.

    Great review AUTUIN! Fun seeing pictures of old PCs like this. You must get a lot of them in your recycling work....:^)

  15. Hi bellarmine --

    Squinting at the pictures of the label, I see "WD93020-IE2-10" and "wd2285". The drive itself, unfortunately, is long gone. Good luck! I can't find much about either of those numbers online.


  16. hi all.

    I have recently gotten a pc like this, but the problem is that I haven´t the boot disk and i can´t do anything.

    anyone know where to get it or someone can send me?.


    my email is:

    There is some link of some MS-DOS 3.21 zenith but no work in the computer:

  17. Hi ... I'm Adolfo PatiƱo and I have a Zenith eazy Pc ... This machine start and boot but I don't have the specific DOS ...Can you help me? ... Please ... I am a high school Teacher and I'd like to show this personal computer to my student ... Thanks a lot for your help ... Muy email is


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