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 and 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: 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.

Also available: Deep Rybka 4