Rybka 4 For years Rybka has been the uncontested number one in computer chess and since its great breakthrough in 2006 the program has won with remarkable regularity one world title after the other. So that this state of affairs will continue in the future, the Rybka-team gathered around programmer Vasik Rajlich has developed a new version which is even better: „Rybka 4 plays more aggressively and more tactically“.

During the last two years the engine has been improved in almost all areas. One major theme has been the understanding of the attack on the king. The new Rybka 4 is in this case more precise and reliable than its predecessor. At the same time the search function now operates more quickly and efficiently and the evaluation function delivers even more spot-on judgments. As for the playing style, Rybka 4 logically continues the development of the past few years. Thanks to further development in the tactical area too, the new Rybka 4 will be indispensable for all those who work and analyse with chess engines. Rybka 4 is delivered with the new user-friendly Fritz 12 interface and contains a database of 1.5 million games and includes CLASSIC membership for playchess. com for one year. System requirements: Minimum: Minimum: Pentium III 1 GHz, 512 MB RAM, Windows Vista, XP (Service Pack 3), DirectX9 graphics card with 256 MB RAM, DVD-ROM drive, Windows-Media Player 9, internet access (playchess. com, updates and activation). Recommended: PC Intel Core 2 Quad, 2.4 GHz, 3 GB RAM, Windows Vista or Windows 7, DirectX10 graphics card (or compatible) with 512 MB RAM or more, 100% DirectX10 compatible, sound card, Windows Media Player 11, DVD ROM drive and internet access (playchess.com, updates and activation). The activation of the program requires internet access.

The Rybka4 opening book is a high-class compilation of opening theory. It was developed for the world‘s strongest chess entity - 100 cores cluster Rybka and program Rybka4 and will maximize the program‘s playing strength. The choice of variations in the book is well suited to the style of the program, and the book has been fine-tuned and checked in thousands of games.

The Rybka Book include 17 million positions and over 700.000 games, which were selected from following sources: TOP human practice, correspondence chess games and computer chess games (up to April 2010). And this is only the starting point: the value of the book lies in over 700 original analysis and move choices, which lead to a re-evaluation in many critical points of modern theory. This makes it useful for tournament and correspondence players alike. The book contains a lot of computer-checked analysis never published anywhere before. The author of the Rybka4 book is Jiri Dufek (national master, FIDE 2276, ICCF IM 2579), one of the world‘s leading experts in chess opening theory. Jiri Dufek has been on the Rybka team since summer 2009, and his preparation is used in all official events after this date, which Rykba won. During World Championship match between Vishy Anand and Veselin Topalov worked as second of Veselin Topalov. In his long chess career he won twice Czech Correspondence Team Chess Championship and wrote together with Roman Chytilek book Beating the French defence (in Czech only). System requirements: Pentium 1 GHz, 512 MB RAM, Windows7, Vista or Windows XP (Service Pack 2), CD ROM drive, WindowsMedia Player 9, Rybka4, Deep Rybka4, Fritz12, Shredder 12 or Hiarcs 12

The new Deep Rybka 4 is in this case more precise and reliable than its predecessor. At the same time the search function now operates more quickly and efficiently and the evaluation function delivers even more spot-on judgments. As for the playing style, Deep Rybka 4 logically continues the development of the past few years. Thanks to further development in the tactical area too, the new Deep Rybka 4 will be indispensable for all those who work and analyse with chess engines. The new multiprocessor version Deep Rybka 4 calculates much faster than the single-core version: when you double the number of processors, Rybka‘s ‚speed‘ increases by a factor of 1.7! Deep Rybka 4 is delivered with the new user-friendly Fritz 12 interface and contains a database of 1.5 million games and includes CLASSIC membership for playchess.com for one year.

System requirements: Minimum: Minimum: Pentium III 1 GHz, 512 MB RAM, Windows Vista, XP (Service Pack 3), DirectX9 graphics card with 256 MB RAM, DVD-ROM drive, Windows-Media Player 9, internet access (playchess.com, updates and activation). Recommended: PC Intel Core 2 Quad, 2.4 GHz, 3 GB RAM, Windows Vista or Windows 7, DirectX10 graphics card (or compatible) with 512 MB RAM or more, 100% DirectX10 compatible, soundcard, Windows Media Player 11, DVD ROM drive and internet access (playchess.com, updates and activation). The activation of the program requires internet access.