derek@uwvax.UUCP (Derek Zahn) (11/25/85)
I recently purchased a Mephisto Modular chess computer by mail order from
an ad in Chess Life and though that some people out there might be interested
in a review.
Price: $299.95
(I am going to skip listing features; the ad lists them)
THE UNIT
The machine itself is pretty nice, even though it is all plastic. It
is very easy to use (the board is auto-sensory [you make your moves
just like you would normally, and it senses where you moved -- it's done
with magnets or mirrors or some such thing....] and every
square has its own LED). It is called "modular" because there are
three edge-card connections on the front. One of these contains the
computer, one an LCD display, and one is unused. These can be rearranged
at will.
CHESS
The program is fairly good, but there are definite differences in style
of play between the machine and a human being. To start, material seems
to be of paramount concern to it [it never gambits a pawn unless its
opening book told it to or it can get it back quickly]. This tends to
lead to positions that are somewhat quiet. It seems to play fairly
accurately positionally, but I get the impression that it does so
rigidly, with a finite number of heuristics like "doubled pawns are bad"
and so forth -- you can be sure that if it can double pawns with an
exchange, it will almost invariably do so. At times, it does appear to
exhibit medium or long range planning, but I suspect that this is mostly
accidental.
The ad claimed that at tournament level (40 moves in 2 hours), it would
play at 2046 strength. I am somewhat doubtful of this, however, since
we seem to be of about equal strength at this speed, and I am rated around
1400 [provisional]. I suspect that the high estimate is based on the fact
that it is very strong tactically, brute-forcing 7 half-moves on all
continuations and more for certain interesting ones at tournament speed.
In all, it provides a good game, and I think it will be invaluable to me
as a tool for improving my chess. It is especially handy for drilling
through opening variations (its opening book is fairly large -- more on this
later....) and analyzing uncommon variations or testing ideas. It is also
quite useful for helping go over tournament games, suggesting alternatives
to moves that I actually made that led to weaknesses.
Now some complaints. First, although the opening book is extensive,
there are some important lines missing. The worst example I have found
so far is the way it treats the Sicilian Defence as White. After
1. e4 c5 2. Nf3 d6 3. d4 cd, it will ALWAYS reply 4. Qxd4 instead of
4. Nxd4. Then follows 4. ... Nc6 5. Bb5 Bd7 and most of Black's
problems are solved with the renewed threat of 6. ... Nxd4. This is
a shame because I play the Sicilian and the blasted machine will not
play the normal variations! (This is not actually that bad, since the
opening can be quite easily entered up to 4. ... Nf6 and then start the
computer, but it still is not aware of the subtleties of this position
that should be incorporated into an opening book)
Also, as White in the Queen's Gambit Declined, Cambridge Springs Defense
(where the black Queen comes out to a5 to put pressure on the knight),
Mephisto gets out of its book and makes moves that lose a queen side pawn,
and in some variations posts its bishop at the insane square d8.
Oh, I also have a complaint about the way it solves problems. If you give
it a mate-in-eight, it thinks for a while (as much as 10 minutes or so),
then makes its move. When you reply, it basically starts all over, and
solves the mate-in-seven instead of just remembering the solution line.
Pretty silly.
Well, that's about it. If anyone out there is thinking of buying one
of these and wants some more specific information, I will be happy to
oblige. And if anyone out there has one, I would be happy to exchange
notes.
--
Derek Zahn @ wisconsin
...!{allegra,heurikon,ihnp4,seismo,sfwin,ucbvax,uwm-evax}!uwvax!derek
derek@wisc-rsch.arpa