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Sigma Chess 6.1 with HIARCS 12 engine

The strongest and best-featured chess software ever for Macintosh computers. Available now!

Sigma GameWare has partnered with the HIARCS team with the goal of bringing you the strongest and best-featured chess software ever for Macintosh computers. See the parallel announcement on the HIARCS Mac home page.

HIARCS 12 is the strongest chess engine ever for the Macintosh, with a playing strength of up to 2900 ELO in the full version!

Requires any Macintosh running Mac OS X (the Classic Mac OS is not supported).

Thanks to Mark Uniacke for bringing HIARCS back to the Mac, and thanks to Richard Fowell and David Gill for all the feedback and beta testing!

Product Configurations

The combined Sigma Chess HIARCS product is available in three different configurations:

1) Sigma Chess HIARCS lite
Sigma Chess 6.1 Lite and the Unregistered HIARCS 12 engine is available in a combined free download, where the HIARCS engine has the following limitations:

• Over 400 Elo weaker than the activated/registered engine.
• Chess Engine search is 10-40 times slower.
• Search depth is limited to 13 plies (one ply is a move for one side).
• Some important evaluation components are disabled.
• Only one CPU core is used.
• No Nalimov endgame tablebase support.
• Achieves about 2500 Elo, strong enough to defeat more than 99.9% of chess players.
• Playing styles and all other configuration options are fixed.
• Only the first 10 moves of the opening books will be playable.
• Hash tables are limited to 16Mb.

2) Sigma Chess HIARCS
Sigma Chess 6.1 Lite and the Registered HIARCS 12 engine gives you access to the following features beyond the Lite version:

• Choice of HIARCS 12 Single or Multiprocessor engine versions.
• HIARCS is a Universal binary to maximise performance on both Intel and PowerPC based Macs.
• Chess strength up to 2900+ Elo depending on your hardware performance and version.
• Full chess brain enabled and 10-40 times faster than Lite version.
• Maximum depth extended from 13 moves to 62 moves lookahead.
• Hiarcs 12 scores 98% v Hiarcs 12 Lite!
• Unlimited levels and time controls: Casual, Blitz, Active, Fischer and Tournament.
• Multiple playing styles, Solid, Normal and Aggressive; together with hypermodern play.
• Configurable Smart Search, Selectivity, Threats and Combination settings.
• Positional and book learning capabilities so Hiarcs improves as it plays.
• Full Tournament book with the latest opening theory for study and preparation.
• Hash tables up to 64Mb. Larger hash tables up to 2Gb are available with the Sigma Chess Pro version.
• Explore new Sigma Chess 6.1.6 GUI with new features like MultiPV.

3) Sigma Chess HIARCS Pro
Sigma Chess 6.1 Pro and the Registered HIARCS 12 engine gives you access to the following extra features from the GUI:

• Settable Elo chess strength in the range (1250 Elo - 2900+ Elo depending on your hardware performance)*.
• Endgame database support of Nalimov tablebases up to 6 pieces for perfect play in the endgame*.
• Support for hash tables over 64Mb up to 2Gb depending on RAM availability*.
• Sigma Chess GUI now supports engine-engine match play.
• Continuous monitor analysis by HIARCS*.
• Full Elo history graph and statistics.
• Game collections of up to a million games including PGN & EPD with search capabilities.
• HTML web page export including "Rules of Chess" collection and diagrams.

*Please note you must have also purchased the HIARCS chess engine in (2) above in order to upgrade to the HIARCS enhanced features above.

IMPORTANT: Sigma Chess 6.1 Pro and the Registered HIARCS 12 engine must be purchased separately. Sigma Chess 6.1 Pro can be purchased online here (it's a FREE upgrade for owners of Sigma Chess 6.0 Pro). HIARCS 12 can be purchased from www.hiarcs.com.

FAQ

Is the registered HIARCS engine included with Sigma Chess 6.1 Pro?
No. The HIARCS engine must be purchased separately from the HIARCS home page.

Is Sigma Chess 6.1 Pro a free upgrade for Sigma 6.0 Pro users?
Yes. Sigma 6.1 should automatically run in Pro mode (otherwise use your existing license info to upgrade).

How does Sigma and HIARCS interface?
Through the UCI (Universal Chess Interface) protocol, which is currently supported by many Windows chess programs.

What about the original Sigma Chess engine?
It is still available for users with ELO ratings way below 2900 :-)

Can I also use HIARCS under OS 9?
No. The HIARCS engine and the UCI interface component in Sigma Chess only runs under OS X.