The Epson Equity 1e is an interesting computer and defiantly worth talking about. Its interesting for several reasons. First off it’s a clone of an IBM PS/2 machine (specifically the IBM PS/2 model 30) that beats IBM at its own game making a clone PC that is superior in almost all ways to its source. Second, it is one of the only known PCs in existence other then the IBM PS/2 line that uses MCGA video. The Epson PSE-30 is also known to use MCGA though I’m unsure at this point if the PSE-30 is simply a rebadged 1e or not. This isn’t necessarily a positive point but it is a point of interest. It also happens to be a very late model using the at this point aging 8086 CPU and I suspect one of the last commercial PC’s to use said processor. It does use the CPU to the best of its abilities and can be made into a very fast and capable PC. I do not know the exact date of commercial release but the manual for the 1e is copyrighted 1988 but this definatly feels like a later early 90’s machine.
The 1e came in a few configurations. Mine is the single 720kb floppy and hard drive version though there were duel floppy versions. The hard drive installed when I received this machine is was not stock. I believe the stock version was a 20MB half height MFM hard drive. The machine itself if fairly compact and of good quality. The downside is the lack of expansion bays. Also both bays are of the 3 1/2 inch variety so no 5 1/4 floppy drives. While were talking about floppy drives, the 1e has a built in floppy controller that can not be disabled so your stuck as far as floppy drives go with 720kb drives though this is usually more then enough for the era of games this machine is meant to play.
There’s a single LED power light to the far left. About mid case we have two recessed buttons. The first is a reset button and next to it is a “Speed” button. The speed button acts like a turbo button on later PC’s though here the labeling actually makes sense. I never could understand the “Turbo” moniker on 386/486 machines as by default the machines ran at their full speed but on pressing the “turbo” button the machines was slowed down, very backwards. Here the labeling makes much more sense with the machine running at a default 8mhz and the speed button giving a modest bump up to 10mhz. This is accompanied by a change in the LED color from orange to green. Finally we have the rather large rectangle power button to the far upper right of the case.
Here’s the back view. Ignore anything in those expansion bays as they would not be present stock. The only card that would be installed stock would be a hard drive controller card IF your configuration included a hard drive. To the left we have the power switch and the fan vent for the PSU. The first port we have from left to right is the built in video port. As I mentioned before the Epson Equity 1e is the ONLY non-IBM PC to use MCGA video. I wrote a Quick Guide to Computer Graphics article awhile back if you want to check that out but in a nutshell MCGA is a cost saving cut down version of VGA. Its uses the same connector and any modern VGA monitor should work fine. MCGA can do 320×200 in 256 colors like VGA but not some of the higher resolution VGA modes. It can also display CGA but it leaves out the ability to be backwards compatible with the EGA standard making it a rather poor choice for this machine since I think the 1e is ideal for EGA games of the late 80’s and early 90’s.
Next to the video port we have two standard PS/2 ports for keyboard and mouse which is really nice on an XT class machine. Its not to often you can so easily use a modern optical mouse on an XT class machine. Lastly we have a parallel port and a serial port though it is the larger version of the serial port so if for some reason you wanted to use a serial mouse you would need a cheap and easy to find adapter.
So lets take a look on the inside. The case is opened by removing seven screws, two on each side and three in the rear.
The inside of my machine was exceptionally clean when I received it. I think it was originally used in a office as the side had a property of Washington county Virginia marked. This machine as you can see uses a nice sized PC speaker and not a beeper. I find it to be pretty good as its not to loud or so soft. Overall the motherboard is pretty compact especially for an XT class machine, showing off the refinements due to the late production date of this machine. Taking a closer look.
1) CPU – The heart of the 1e is an 8086 processor. In this case an AMD version. The 8086 was the true 16 bit brother of the far more common 8088 found in the original IBM PC and many, many clones. The 8086 is 100% compatible as far as I know with software for the 8088. Where the 8088 was 16 bit internal but only 8 bit external the 8086 was 16 bit both internal and internal giving it in some cases a 50% speed improvement over the 8088 running at the same mhz speed. Some motherboards featureing the 8086 still had a 8-bit logic board but the motherboard in the 1e has a fully 16 bit data bus and 0 wait states taking advantage of the power of the 8086. The speed of the CPU is one of the reasons I find this machine more tailored to EGA games rather then CGA as many CGA games, especially early ones tended to be very dependent on the 4.77mhz speed of the standard 8088 and a 8mhz 8086 or especially a 10mhz 8086 can cause these games to run far to fast. Even a number of early VGA games can be made to run acceptably on the 1e.
2) Co-Processor socket – This is a socket for an optional 8087 math co-processor. Because of the 10mhz speed you would ideally want a 8087-1 co-pro that is rated for 10mhz. an 8087 wont find much practical use in this machine unless you love running CAD stuff but there are a few games like Sim City that will benefit from it.
3) RAM – This is the built in 640kb of system RAM. This should be more then enough for running all the games this machine is tailored for. For additional RAM you would need to find an add on RAM expansion card though almost no games of the period will require or take advantage of this.
4) CMOS battery – This machine uses a battery type I’ve not seen in any of my other machines. This is a barrel style Lithium battery. Most PC’s of the time used a Nic-Cad barrel battery. later machines used a coin style Lithium battery. Thus far the battery has worked perfect and shows no signs of leakage. not bad for two plus decades.
5) Floppy connector – The built in floppy connector. It even has the plastic guide siding that wasn’t even common until the socket 7 era and wasn’t even common on high end 486 motherboards. The big downside of the built in floppy connector is that it cannot be disabled so there’s no chance of upgrading the floppy drive to a high density 1.44mb drive.
6) Riser slot – the riser card for this machine supports four 8-bit ISA cards which is one more then the IBM this machine is cloned off of.
The build quality of the Epson Equity 1e is impressive and is a pinnacle of XT class technology. The MCGA is a major drawback as the machine stock is a little to slow for later VGA stuff. a true VGA or EGA card is really needed to unlock the potential of the 1e. Its a unique PC and one I’ve enjoyed using. with a VGA card I’ve found it fills a small niche for EGA games that won’t run on my CGA 8088 machine but run a tad to fast on my 10/20mhz 286 PC such as Ultima: the First Age of Darkness and Ultima II with the EGA patch applied. The manual and spec sheets for the Equity 1e can still be found here.
SUGGESTED UPGRADES
To really unlock the potential of this machine I performed a few upgrades. I even considered using this machine as a templet for a “Anatomy of a 8086” article but have decided against it (though expect an “Anatomy of a 8088 PC” in the future). A VOGON’s user Anonymous Coward did build a very nice and far more capable 8086 based machine similar to this one you can read about here. For the 1e though I have made the following upgrades.
CPU – My first upgrade was to the CPU and this was to replace the 8086 with a pin compatible NEC V30. the V30 is very much like the 8088 upgrade V20 chip. the V30 is almost 100% compatible with 8086 software and is a simple drop in replacement. You can expect an immediate 10 – 15% speed boost, more in some cases. The V30 should bring the CPU power of the 1e very close to that of a 286 machine. Running at 8mhz Landmark speed test ver. 6.00 reported I was running equivalent to a 9mhz 286 CPU but this can be taken with a grain of salt. Another benefit of the V30 is that is contains some 186 code allowing some software meant for a 286 to run. Next to a true VGA card I think the V30 upgrade is essential for smoothly playing EGA and VGA games on the 1e though keep in mind compatibility due mostly to increased speed will decrease for older games, especially CGA ones.
I also did some benchmarking using CheckIt 3.0 and ran this machine at the 10mhz turbo setting up against my IBM model 30 286 sporting a true 10mhz 286 with these results
IBM Model 30 286 w/ 10mhz AMD 286 = 1889 Dhrystones
Epson E1 w/ 10mhz NEC V30 = 1280 Dhrystones
So the results confirm the V30 is still behind a true 10mhz 286 but its definitely in the ball park and I would wager about equal to an 8mhz 286
The V30 I got here is rated for a whopping 16mhz. The 1e will only run it at 8 to 10mhz but my thinking is with the higher tolerance it should run a little cooler (though overheating is not really a concern at these speeds).
Co-Processor – I hate empty sockets on a motherboard so I purchased an Intel 8087-1 math co-processor for this machine. It probably won’t get much practical use for games but it makes me warm inside knowing its there.
Video card – You NEED to install a VGA card to really enjoy the 1e fully or at least an EGA card if you have the correct monitor. This machine really excels at EGA era games and even stock at 8mhz is to fast for many CGA titles. The trick is finding an 8-bit VGA card as the 1e only supports four 8-bit ISA slots. I found the easiest solution was to find a 16 bit VGA card that runs in 8-bit slots. Surprisingly there are a number of them to choose from. The Vintage Computer Forums have a post on which 16-bit cards work in 8-bit slots here. I found that I had a Trident 8900D based card in my box of unused cards and it is the card I’m currently using. The card is a full VGA card and has 1mb of video RAM, more then the PC. The card was configurable to 8-bit mode by configuring a few jumpers. Trident is usually known for low end video cards and I usually do not recommend them but the 8900D chip actually does very well in benchmarks I read and is possibly the best of there cards for the task. The 8900C based cards supposedly auto detect if your using 8 or 16-bit slots but are much slower cards. Though at XT class speeds the extra RAM and speed probably does not matter much.
Hard Drive – My 1e actually came with a fairly rare XT IDE hard drive controller from Silicon Valley, the ADP50L and is primarily the reason I bought this machine. Its a pretty capable controller that allows more modern IDE drives to be used in PCs with only 8-bit slots much like the IDE-XT hobbyist cards today. The stock hard drive as I mentioned before was a 20mb half height MFM drive but mine came with a 52MB IDE drive along with the controller card. I ended up replacing this rather small and oddly sized drive with a 420mb IDE drive I had sitting around. It didn’t have the fancy front plate with the activity LED so I ended up having to fashion a new front plate from a discarded bezel plate of another PC.
Sound Card – For sound I went with a Sound Blaster 1.5 w/ added CMS chips that I recently acquired from a trade. This card is sound blaster compatible as well as mostly CMS sound compatible thanks to the add on chips.
All these upgrades together greatly increase the power of the Equity 1e and open up many possibilities for smoothly running EGA and some VGA games. A possibly better VGA card (though honestly the 8900D is surprisingly a fast card), larger or faster hard drive and maybe the inclusion of a EMS memory card for that empty fourth expansion slot could make this PC even more capable I found that it now occupies a nice place for me playing EGA games that are to fast for my 8088 but run to fast for my high end 286.
ancientelectronics 
8 Comments
so, what ega games do you recommend?
pretty much anything that meets system requirements. depends on what kind of games you like. so far I’ve played the 87 Ultima 1 PC port and Ultima II with the fan EGA patch. should play early adventure EGA games like the early kings quest/space quest games no problem. I know with a video card and a nec30 upgrade later stuff like Monkey Island even becomes playable. If I get around to it I may make a video of the machine playing some stuff.
Nice machine. MCGA is fine IMO. I played many games on my PS/2 Model 30 8086 with MPU-401 and MT-32. I did upgrade to a V30 to improve performance.
MCGA does get the job done but when upgrading to full VGA via a card is so easy and cheap its almost like why wouldn’t you? unless your short on expansion slots I guess.
Hi,
You keep saying it’s the only non IBM MCGA. This is not true, the EPSON PSE30 was also MCGA. Both were almost identical, I can’t just see a small design difference. Inside seem to be the same.
Good review though.
very interesting. None of my research prior mentioned this machine nor did any of the very savoy people over at the vintage computer forums. doing a google search reveals very little information on this model and most of the pages seem in Spanish. It seems it was a fairly uncommon model and looks identical. Perhaps it is simply the model name they gave to the 1e outside of North America Thanks for the info, I’ll adjust the article. do you have any other information on this model? did you own one?
I’m interested in corresponding because I have a theory that Seiko-Epson designed the PS/2 Model 30 for IBM – then were released to be able to offer their version later (or in non-competing markets). There is a planar features control register at port 65h that is bit-for-bit the same without any reason to mimic it. The FDC can be disabled, but try plugging in a 1.44Mb drive – It should work, exactly like that process does for the PS/2 Model 25 and 30. It also appears that Seiko-Epson was involved in designing the VGA standard for IBM as well.
Awesome article! Kudos! ^^
There’s just one thing I would like to mention.
Early ISA VGA cards had dedicated emulation modes for CGA, EGA, Hercules.
Especially for CGA, they added low-level functions (alternate palettes via registers etc).
However, they must be activated manually through a ‘mode utility’ (part of the VGA’s floppy).