Testing old chess computers through emulation

In the days before everyone had computers, if you wanted to play chess, your only option was to play with another person. In the late 1970's Fidelity introduced a series of electronic computer chess games. These early models played rather poorly, but I knew people who bought them just to be able to play and practice whenever they wanted. I managed to borrow a few of these so that I could get a feel for how well they played.

Although the early machines did not play well, things started to improve in the 1980s. In 1984, I purchased the Novag Super Constellation electronic chess game for what I think was $200, which was quite a bit of money in 1984. The U.S. Chess Federation had given it a rating of 2018, which is better than at least 90% of all adult tournament players. Any rating between 2000 and 2199 is considered to the skill level of "Expert" and a higher rating of 2200 is considered to be "Master."

Although I am currently rated 2016, at the time I bought the Novag Super Constellation I was rated just a little over 1700. In a few months, I would reach a rating of 1800 which is considered "Class A." Nevertheless, what I remember about the Novag Super Constellation is that it played better than me, which is surprising since it only contains an 8-bit processor running at just 4 MHZ. That is not very fast compared to modern 64-bit processors with multiple cores running at gigahertz speeds.

Over time, I bought a couple of better chess-playing computers and I have fond memories of practicing with all of them. I sold all these machines when I got a desktop computer in the mid-'90s, but I kind of regret it because they all were fun to play with it.

This became an issue when I was researching these old chess-playing computers where I saw many online claims that these computers were not as good as the ratings that had been assigned to them. For example, I saw the claim that the Novag Super Constellation was only about 1750 strength, and two other computers that I owned rated 2100 and 2265 were also claimed to be weaker than their advertised ratings. None of these claims match my experience, since all of the computers played better than I did.

I was so curious about this that I wanted to get my hands on one of the old chess computers, assuming that one can be found, which is unlikely, and see how it compares to my current chess ability. Fortunately, I found software that allows me to emulate dozens of old chess computers on my Windows PC.

In my first game against the emulated Novag Super Constellation on level 1, the lowest level, I was able to win by only the slimmest of margins. I tried the same thing on the Fidelity Designer 2100, a slightly better machine, and I lost. I have no doubt that the other computer I owned, the stronger Fidelity Designer 2265, would stomp me like it used to when I played it 30 years ago. I will confirm this eventually.

So I tested a variety of chess computers with a somewhat difficult chess problem..

Most serious chess players have seen this problem already and know the answer. However, if they were not familiar with it, the solution might be difficult for them to find in a real game. There is the more direct solution of 6. Nxe5 Bxd1 7. Bxf7+ Ke7 8. Nd5# (checkmate). However, for a computer to see the solution it also has to see 6... Nxe5 7. Qxh5 Nxc4 8. Qb5+ c6 9. Qxc4. There is also 7... Nf6 8. Qe2 Nxc4 9. Qxc4. Either way, that is 7 half-moves deep, which is pretty deep for ancient chess computers to look.

Based upon my testing, this is how long various chess computers took to solve this chess problem...

Model Year Procesor Speed ROM Time Depth Nodes/S
1. Fidelity Chess Challenger 10
2. Fidelity Chess Challenger 7
12 hours
3. Super Constellation
5 ply
4. Fidel. Designer Display 2000
5 ply
5. Fidel. Designer Display 2100
5 ply
6. Fidel. Designer Display 2265
16 MHZ
3 ply
7. Chessmaster NES
1.79 MHZ
5 ply
8. Chessmaster Super Nintendo
3.58 MHZ
5 ply
9. Stockfish 14.1 2017-iMac
3.4 GHZ
12 ply

It is noteworthy that the Super Constellation solved the problem in roughly 2 minutes, which is within tournament time controls. I am disappointed in Chessmaster on the Super Nintendo because it failed to achieve this. It is running on a similar processor, and it is a port of Chessmaster 2000 written by Dave Kittinger, who also wrote the Super Constellation program!


French McCutcheon



Play chess online


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From a game of mine around five years ago. This is not difficult. I had a little problem seeing the continuation to mate, but now I can't imagine why I found this difficult at all. It appears to me that there are at least a couple of ways to do it. Even if I didn't see the moves to the end, I still would have made the same moves at the beginning. Any decent chess player would.



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Around 1858 Paul Morphy came out of nowhere to beat the top players in the world. Then a couple of years later he gave up chess claiming it was a waste of time.  Bobby Fischer called Morphy "the greatest genius of us all."

Best wishes,

John Coffey

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Magnus again ...


Best wishes,

John Coffey



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He paid me an exceptionally nice compliment when he said, "I thought that I was a good endgame player, and then I played John Coffey and I found out what a really good endgame player is."


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Nepo's rating hasn't changed.


World Chess Championship

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For Magnus, it's inevitably getting difficult. It's already his fifth match, so I don't think the fire is burning so hard inside.
—Vishy Anand