| Frequently Asked Questions:
Why do I get a "No opening book" message?
You are wondering why the product keeps telling you "WARNING: no opening book" each time you launch it.
Like most chess players, Chess Tiger plays the first moves of any game "by heart". The starting position of chess has naturally been studied extensively since centuries, and there are known good ways of starting a game.
There are good ways of playing the very first move of the game, as well as good ways to answering to this first move. And also good known answers to this answer, and so on...
The knowledge about these opening moves is stored in an "opening book".
The opening book of Chess Tiger is a file named BOOK.PDB.
When you installed Chess Tiger on your handheld, you forgot to install book.pdb together with chesstiger.prc.
You can install this file now. Chess Tiger will stop complaining about its opening book.
Now when you start Chess Tiger on your handheld, it should not say anything anymore about its opening book.
Using Chess Tiger:
It must be noted that the version of
Chess Tiger that has been tested by the SSDF is version
14.9 using only 48Kb of hash tables. The current version
is 15.0 (with a significantly improved chess engine) and
is able to use up to 12Mb of hash tables. We believe
that version 15.0 is at least 50 elo points better than
the version tested by the SSDF and thus would achieve a
rating of at least 2150 elo (comparable to 2150 FIDE elo
or 2350 USCF elo).
The other numbers mean that
Chess Tiger is number 135 in their list (the list
includes chess programs running on extremely fast PC
hardware, and the PC version of Chess Tiger is
currently in third position). ChessGenius is number
182. The rating of Chess Tiger is 2101 elo (the SSDF
elo is comparable to the FIDE elo, to get the
corresponding USCF elo you should add 200 points).
The rating of ChessGenius is 1870. Both Chess Tiger
and ChessGenius have played 100 long time controls
games (40 moves in 2 hours) to achieve their rating.
The margin of error for Chess Tiger is +69, -74 with
95% reliability. The margin of error for ChessGenius
is +69, -78 with 95% reliability. Chess Tiger has
achieved a score of 39% against an average
opposition of 2180 elo. ChessGenius has achieved a
score of 32% against an average opposition of 2002
You can find the official SSDF list here (click on "download the list in DOS format" to find the ratings quoted above).
The SSDF is an independent Swedish organization. They have been testing chess computers and chess programs for more than 16 years now. They are universally regarded as the most reliable source of information about the strength of chess computers and chess programs.
Before the SSDF data was available, an
independent tester contacted us and offered to test
Chess Tiger against ChessGenius. You can find the result
of his 26 games match here.
The ELO system compares the strength of the chess players and rates them.
The ELO system is not an absolute scale. It does not give any idea about the absolute strength of a player. It only gives an idea about the relative strength of a given player inside a "pool" of rated players who have played against each other.
For this reason, the elo of a player cannot be
used directly to compare the strength of this player
with the strength of a player from a different "pool".
This is similar to the difference between miles and
kilometers, or centigrade and Farenheit degrees.
For example, the elo of american players (also
called USCF elo) cannot be compared directly to the elo
of european players (FIDE elo). An american player rated
2000 USCF elo is not at the same level than an european
player rated 2000 FIDE elo.
It is generally admitted that you must subtract
200 points to the elo of an american player (USCF elo)
to get its equivalent in FIDE elo. This is just a rule
of thumb that is highly debatable. This rule gives a
rough estimate and has a limited range of validity (its
validity is limited approximately to the 1700-2400 USCF
So a 2200 elo american chess player is
approximately of the same strength as a 2000 elo
You should not try to deduce anything from this difference. It is a normal effect of the ELO system which, let us restate it, does not provide an absolute measure of strength, but just a measure of the relative strength of a player inside his "pool". As the "pool" of players used to build the USCF elo is distinct from the pool used to build the FIDE elo, it is expected that a direct comparison between the two is not possible. In other words, both elos are not calibrated against each other, and so are likely to "drift" over time. That is exactly what has happened.
What is the ELO rating of Chess Tiger, and what does it means?
The elo rating of Chess Tiger playing at full strength is 2300 USCF elo (american scale), or approximately 2100 FIDE elo (european scale) on a standard 20MHz PalmOS device. This excludes the trainer levels which have been designed to play weaker (read about the trainer levels here).
What does this mean exactly?
It means that if you let Chess Tiger running on a
20MHz PalmOS device and a 2300 USCF elo human chess
player (or computer) play a very long series of long
time controls games (each player is allowed to play 40
moves in 2 hours), you will get an approximately even
result, no player being able to demonstrate any
superiority on his opponent.
NOTE: this elo rating can be achieved only with a
reasonable amount of hash tables: at least 3Mb for long
time controls games.
The experiment has not been done, so it is not
possible to give a definite answer. However we believe
that the strength of Chess Tiger does not vary
significantly when you change the time controls. It does
not mean that Chess Tiger playing blitz is as strong as
Chess Tiger playing at long time controls (when you give
it more time to think Chess Tiger plays stronger). It
means that Chess Tiger playing blitz would probably play
at the same level as a 2300 USCF elo chess player
What happens if we change the speed of the
With the experience accumulated by the SSDF
association and the rating lists they have published
since 1985, it has been possible to conclude that
doubling the speed of Chess Tiger would add
approximately 70 elo points to its elo rating.
Similarly, slowing it down by a factor of two would
subtract 70 elo points to its elo rating.
Please note that this rule does not apply to a
human chess player. Also, it does not apply to all
computer chess programs (some programs do not benefit
equally from a speed increase). We just claim that this
rule applies to Chess Tiger, with a good reliability, in
the 1800 to 2800 USCF elo range.
By extension, multiplying the speed by 4 adds 140
elo points to the strength. Multiplying the speed by 8
adds 210 elo points.
The general formula is:
The base of the logarithm function does not
matter. You can use indifferently a logarithm of base
10, of base e, of base 2 or whatever.
To evaluate the speed of a computing device, one
should NOT rely on the MHz figures. The computing speed
of a PalmOS device generally does not vary linearly with
the clock speed. The speed of a given PalmOS device
should be measured with the "Speed index" feature of
The speed index measured by Chess
Tiger 15.0 on a standard 20MHz PalmOS device is
So if you want to know the exact elo rating of
Chess Tiger on your PalmOS device, use the following
This is almost similar to changing the speed of
the device. If you allow yourself twice the thinking
time allowed to Chess Tiger, you artificially reduce the
strength of the program by 70 elo points.
NOTE: in this case you should disable the "Turbo
mode" feature of Chess Tiger to prevent the program to
think while it is your turn. Disabling the Turbo mode
has the additional effect of reducing the playing
strength by approximately 30 elo points.
Does Chess Tiger for Palm have an opening book?
Yes, it knows "by heart" a lot of opening moves. At this time it knows approximately 8000 opening moves.
You can learn some of the most popular openings by letting Chess Tiger play them for you.
The opening book is separated from the
chess engine, so you will be able in the future to
download updated opening books from www.chesstiger.com
and to install them on your Palm without the need to
reinstall the entire program.
Yes, Chess Tiger will try to avoid
replaying an opening it has lost recently. So you won't
be able to beat it by playing the same game over and
Yes it is!
Chess Tiger can read and save games in "PGN" format. This format is a worldwide standard for chess games. Here is an example of a game saved in "PGN":
The great thing with PGN is that it is a "text" format: it is not only readable by a computer, but also by humans like you and me. The text above has been produced by the "Save game" command of Chess Tiger, and has been directly saved into the MemoPad application.
This memo can be read later by Chess Tiger itself.
When you press the HotSync button, all your games are automatically copied to your PC or Mac.
And as "PGN" is a standard format, this game can be read by any PC or Mac based chess program.
Likewise, you can save a game in PGN format with your PC or Mac favorite chess program, copy/paste it into the Palm desktop application, and it will be transferred to your Palm the next time you press the HotSync button.
And Chess Tiger for Palm will be able to read it.
Here are some detailed explanations about this process:
Palm ---> PC/Mac
You can transfer a game saved in PGN format to most commercial chess programs running under Windows or MacOS. Here is how to do it:
It is the opposite operation.
Does Chess Tiger for Palm use hash tables (also called "transposition tables")?
Yes it does. And since version 15.0, you can even select the amount of hash tables you want to use (any amount between 12Kb and 12Mb).
Hash tables are extremely important in the endgame. Programs without hash tables are weak in the endgame. But hash tables also help the program at any stage of the game.
The hash tables can be viewed as a sort of "cache" memory. They work a little bit like a disk or memory cache and help the program to compute faster by keeping recent calculations in memory instead of having to re-compute them when they are needed again.
By making the program faster, they also make it stronger.
Yes! Most Palms can run twice faster than their default speed.
THERE IS NO WAY THAT YOUR PALM CAN OVERHEAT WHEN YOU OVERCLOCK IT. The processor in the Palm consumes so little power that it simply cannot happen, even at the highest speeds.
So you cannot damage your Palm by overclocking it. And in order to overclock you do not even have to open your Palm. It can be done with a software utility called "AfterBurner" (version 3.1 or higher, you can find it at PalmGear: http://www.palmgear.com).
Before you try to overclock, you should perform a HotSync operation, so your data is safely backed up to your PC/Mac.
Overclocking too much can in some cases block your Palm and erase its data. Actually when you experiment with overclocking that's exactly what you want to do in order to know the upper limit your Palm can stand.
When you have found this upper limit, press on the reset button that is at the back of your Palm with a pin. If your data has been erased, just HotSync again and everything will be put back into place.
Reinstall the overclocking program if necessary, and set it to the highest speed that did not hang your Palm.
You are done!
Is there a limit to how much you should overclock?
No absolute limit. As stated above, you should try it by yourself and see at what speed it freezes. If it ever freezes... My m505 runs at 54MHz (the highest speed you can set with AfterBurner 3.1) and never crashed.
Has anyone had any problems with overclocking?
The only problem is that if you overclock too much (even without crashing the Palm) the internal clock could be off. The problem occurs because the internal device that generates the frequency cannot reach the speed you have set, but AfterBurner believes it can, and tries to adjust the clock accordingly.
When it happens, the Palm believes that the time passes more slowly than it does in reality. The clock in Chess Tiger runs too slowly.
In this case all you have to do to fix this is to decrease the speed with AfterBurner (actually your Palm will run as fast, but this time will be well informed about its real speed).
How to do that?
1) overclock your Palm as explained above with AfterBurner 3.1 or higher. Note that AfterBurner is free for speeds up to 37MHz. If your Palm can go higher, you have to buy the registered version of AfterBurner ($9). It will allow you to try frequencies of up to 54MHz.
2) Download Chess Tiger from http://www.chesstiger.com (click Here). Install it on your Palm (it will be in demo mode until you actually pay for it, but for the experiment we want to do it does not matter).
3) Start Chess Tiger and play the first move of a new game (this will start the players clocks). Compare Chess Tiger's clock with a REAL clock.
4) If Chess Tiger's clock run too slowly, you have to decrease the frequency with AfterBurner and go back to step 3.
When you have finished this procedure,
your Palm is OPTIMALLY overclocked!
Here is a preliminary version of a list compiled
with the help of our beta testers:
The TigerMark index (speed index) for various versions of Chess Tiger and various hardware:
(norm means a Palm at its normal speed, ovcl means an overclocked Palm)
Chess Tiger 14.9a
Chess Tiger 15.0,
15.1 and 15.2 for Palm:
Palm Zire 16MHz (norm) 0.35 2062 SSDF elo (2262 USCF)
Palm m105 16MHz (norm) 0.37 2068 SSDF elo (2268 USCF)
Palm Vx 20MHz (norm) 0.45 2087 SSDF elo (2287 USCF)
Visor Deluxe 33MHz (norm) 0.51 2100 SSDF elo (2300 USCF)
Palm V 20MHz (ovcl) 0.51 2100 SSDF elo (2300 USCF)
Palm IIIc 20MHz (norm) 0.58 2113 SSDF elo (2313 USCF)
Palm Vx 20MHz (ovcl) 0.66 2126 SSDF elo (2326 USCF)
Palm m125 33MHz (norm) 0.71 2133 SSDF elo (2333 USCF)
Palm IIIc 20MHz (ovcl) 0.73 2136 SSDF elo (2336 USCF)
Palm m500 33MHz (norm) 0.71 2133 SSDF elo (2333 USCF)
Palm m505 33MHz (norm) 0.75 2139 SSDF elo (2339 USCF)
Palm Tungsten-T 144MHz (norm) 0.75 2139 SSDF elo (2339 USCF)
Palm Tungsten-E 144MHz (norm) 0.81 2147 SSDF elo (2347 USCF)
Palm IIIc 20MHz (ovcl) 0.83 2149 SSDF elo (2349 USCF)
Palm Zire 28MHz (ovcl) 0.86 2153 SSDF elo (2353 USCF)
Palm Zire 71 144MHz (norm) 0.88 2155 SSDF elo (2355 USCF)
Palm V 28MHz (ovcl) 1.01 2169 SSDF elo (2369 USCF)
Palm Vx 28MHz (ovcl) 1.01 2169 SSDF elo (2369 USCF)
Palm V 28MHz (ovcl) 1.02 2170 SSDF elo (2370 USCF)
Palm m125 46MHz (ovcl) 1.05 2173 SSDF elo (2373 USCF)
Palm IIIc 26MHz (ovcl) 1.10 2178 SSDF elo (2378 USCF)
Palm Vx 28MHz (ovcl) 1.12 2179 SSDF elo (2379 USCF)
Palm m125 50MHz (ovcl) 1.17 2184 SSDF elo (2384 USCF)
Palm Vx 33MHz (ovcl) 1.29 2194 SSDF elo (2394 USCF)
Palm Vx 32MHz (ovcl) 1.30 2194 SSDF elo (2394 USCF)
Palm m505 54MHz (ovcl) 1.33 2197 SSDF elo (2397 USCF)
Palm IIIc 33MHz (ovcl) 1.37 2200 SSDF elo (2400 USCF)
Palm Vx 37MHz (ovcl) 1.45 2206 SSDF elo (2406 USCF)
Sony TJ25 200MHz (norm) 1.46 2206 SSDF elo (2406 USCF)
Sony NR70V 66MHz (ovcl) 1.58 2214 SSDF elo (2414 USCF)
Sony T675 66MHz (norm) 1.62 2217 SSDF elo (2417 USCF)
Palm Tungsten-E2 200MHz (norm) 1.62 2217 SSDF elo (2417 USCF)
Palm Zire 31 200MHz (norm) 1.66 2219 SSDF elo (2419 USCF)
Sony NX70V 200MHz (norm) 1.71 2222 SSDF elo (2422 USCF)
Sony NX70V 200MHz (norm) 1.72 2223 SSDF elo (2423 USCF)
Palm Zire 22 200MHz (norm) 1.77 2226 SSDF elo (2426 USCF)
Sony T675 74MHz (ovcl) 1.94 2235 SSDF elo (2435 USCF)
Palm Zire 72 312MHz (norm) 2.64 2266 SSDF elo (2466 USCF)
Palm T|X 312MHz (norm) 2.71 2269 SSDF elo (2468 USCF)
Palm Tungsten-C 400MHz (norm) 3.45 2293 SSDF elo (2493 USCF)
Palm Tungsten-T3 400MHz (norm) 3.45 2293 SSDF elo (2493 USCF)
Palm Tungsten-T3 472MHz (ovcl) 3.93 2306 SSDF elo (2506 USCF)
Palm Tungsten-T3 592MHz (ovcl) 5.01 2330 SSDF elo (2530 USCF)
Chess Tiger 2010 for Palm:
We are currently collecting data for this new version. At this time the best estimate is that Chess Tiger 2010 is approximately 60 elo points stronger than Chess Tiger 15.x on the same device.
Feel free to send us your
results (please send the Palm model name, the
CPU frequency in MHz if you know it and the displayed
speed index on this device).
(last updated 2019/10/22 - a huge thank you to
JC for all these results!!!)
If you want to improve your chess we
advise you to visit the chess
What people say about Chess Tiger:
"Itís easily the best chess program on the Palm OS."
- Handheld Computing
"By far and away the best chess program for Palm..."
- David Dunbar, Chess guide for About.com
"The most powerful and flexible chess program offered
for Palm PDAs is Chess Tiger for the Palm."
- Chris Kantack's LCD Chess Information Site
"I have purchased and installed chess tiger on my Sony Clie UX-50. It is an awesome product."
-- Bob (San Diego, CA, USA)
"Thanks very much. Chess Tiger is a great program :)"
-- Peter (Christchurch, New Zealand)
"I purchased Chess Tiger and love it"
-- Jim (Easton, PA, USA)
"Thanks for a great program, you've done a really good job. Thanks again and keep up with good work!"
-- Marek (London, United Kingdom)
"I love your chess program!!"
-- Tim (Baltimore, MD, USA)
"Hi there, am really enjoying using Chess tiger"
-- Steve (Melbourne, Australia)
"I recently purchased Chess Tiger for my palm tungsten E. Great program :)"
-- Yoram (Forest Hills, NY, USA)
"I downloaded the new version 15.1 for my palm a few weeks ago (I'm a registered user). Congratulations - the new set of pieces is brilliant and I like the whole program a lot"
-- Tobias (Kleinmachnow, Germany)
"About 9 months ago I changed jobs and lifestyle. I sold my Palm and all my Palm software with it, including my license to Chess Tiger. Much time passed, and after a while I realized that I missed having my little pocket chess program with me everywhere I go! So the other week I decided to buy another PDA. The sole reason for making the purchase was so that I could bring Chess Tiger with me everywhere I go! Now I am happy again, as I have a new Tungsten E with the latest version of Chess Tiger on it, and I can bring it with me wherever I go. I can get a quick game in at the coffee shop or on the road. Chess Tiger continues to be the best electronic game of chess out there. Keep up the good work!"
-- Nate (Minneapolis, MN, USA)
"I have handed over my Palm/Chesstiger to my 10-year-old Thomas. He plays day-in-day-out!"
-- Hans (Belp, CH)
"Anyway chesstiger is the best chess program I've seen and I'm glad I ran across it. It's much better than a physical electronic board."
-- Robert (USA)
"I am a lover of chess and I like the ChessTiger very much"
-- Surya (India)
"Have played Chess Tiger and love it"
-- Ray (Cherry Hill, NJ, USA)
"I've bought Chess Tiger and I'm really happy I did."
-- Gilles (Rimouski, Quebec)
"Chesstiger is great!"
-- Glen (Des Plaines, IL, USA)
"Your software is fantastic !"
-- Michel (Saint Malo, France)
"I love the Chesstiger program for my handheld"
-- Harold (Thompson, MB, Canada)
"Thank YOU! It works great... This is truly a great program!"
-- Elmar (Middle Village, NY, USA)
"Your software is really great. I already had bought a chess game for my palm but yours is miles better."
-- John (Barcelona, Spain)
"Chess Tiger is really very good."
-- Jean-Marie (Havelange, Belgium)
"I just downloaded the trial version of chesstiger. I am impressed!"
-- Joel (Manteca, CA, USA)
"I got chess tiger with my Palm Tungsten E, it is fantastic."
-- Juan (Naucalpan, Mexico)
"I am definitely VERY happy with Chess Tiger."
-- Wayne (USA)
"Awesome program. I just bought a Novag Star Sapphire handheld and it was HORRIBLE in the visibility, graphics and ease of use department. Had to return it right away. $230. Got a Palm Vx for free (someone was throwing it away) and put Chess Tiger on it. Palm + Chess Tiger is the ONLY way to go. Love it!!"
-- David (Eden Prairie, MN, USA)
"Hi ingenious people at Chess Tiger. What a great piece of software Chess Tiger is!"
-- Paul (St John's, NF, Canada)
"Your chess engine for Palm Tungsten is great. I had it play chessmaster for fun and it won every time, it is clearly superior."
-- Tim (New York, NY, USA)
"I have been using Chess Tiger on a Palm M130 for about a year now. I really like it a lot and usually find time while working (I'm a teacher) to get in a game or two. I play on it's trainer levels to give me a chance to beat it."
-- Scott (Palm City, FL, USA)
"Hi... Just bought your ChessTiger program for my Palm Tungsten-T3. Excellent!"
-- Andrew (Roslyn, NY, USA)
"Thanks for a great program!"
-- David (Huddersfield, United Kingdom)
"Just bought Chess Tiger and love it!"
-- Christopher (New York, NY, USA)
"Chess Tiger was the reason I chose to buy a Palm OS handheld."
-- Ian (Long Valley, NJ, USA)
"Chess Tiger is exactly what I've been looking for. It is easily worth double what you're charging!"
-- Bob (Haltom City, TX, USA)
"Hi, thanks for the great chess software that has given me many great hours of playing, and has helped me slowly develop my chess game (I'm at trainer level 7 when playing white and 6 when playing black now)."
-- Tien (Arlington Heights, IL, US)
"As a registered user, I love this app, and its wide range of compatibility with all Palms."
"You guys are the best!"
-- Frank (Oslo, Norway)
"I recently registered Chess Tiger 15.1 for the Palm OS. An I can tell you, I love it. it plays strong chess and I am thankful for the trainer levels."
-- Wybren (Oosterhesselen, The Netherlands)
"I want to thank you for creating a very nice product."
"Chesstiger is definitely the best chess programm available for PDAs."
-- Axel (Germany)
"I'm impressed with the product and your support."
-- John (Southampton, United Kingdom)
"I have bought ChessTiger for Palm and it's a wonderful program. Congratulations!"
-- Tiago (Aracaju, Brazil)
"Thanks! Your program is one of the best arguments for owning a Palm!"
-- John (Cincinnati, OH, USA)
"On a side note, I've recently purchased a T2 (from my old M500) and the game is just so beautiful now. The developers did a great job making the most of the color."
-- Brian (Atlanta, GA, USA)
"I have bought Chess Tiger (through Handango) and I think it is a terrific software, even better than other softwares that I have tried on my desktop."
-- Filippo (Raleigh, NC, USA)
"I want to thank you all, first for developing such a powerful engine, and nice interface; and second, for beign a truly serious enterprise, at first I wasn't sure you would help me out, but you did! And I'm very glad to be one of your proud customers, keep up the good work and thanx for making my night shifts less painful again!!!"
-- Eduardo (Quito, EC)
"I think Chess Tiger is awesome! It's my favorite chess program and the first game I put on my new Zire 71."
-- Mike (Muncie, IN, USA)