This is a modified compile of Stockfish 11 (“Stockfish 11 C0”) for Windows that sets the default contempt to ‘0.’
Download it at:
The official Stockfish 11 is set with a default contempt value of ’24’ (24 centipawns), which may increase engine ELO in games against weaker engines, but isn’t helpful for serious analysis.
Stockfish 11 also includes a “dynamic contempt” factor. This remains unchanged in my compile, although I may try to use Dann Corbit’s code to remove it in the future. You can see details regarding “dynamic contempt” here:
You can always change the contempt value in the UCI options if you want to tinker with different settings. See:
With this compile, however, I have removed the need for anyone to modify the UCI options. I suspect the official version with contempt=24 ‘enabled’ will be stronger in engine-engine play, but those interested primarily in analysis might consider using this compile as well.
Because the file name and internal name are different from the official release, you should be able to install it in ChessBase / Fritz as a separate engine and without any problems.
Two changes to the official Stockfish 11 source code are included in this compile:
o[“Contempt”] << Option(24, -100, 100);
o[“Contempt”] << Option(0, -100, 100);
in ucioption.cpp line 63
const string Version = “11”;
const string Version = “11 C0”;
in misc.cpp line 59
The official source code is available at:
It is also provided in this zip file.
Which version should you use?
stockfish_11_C0_x64_bmi2.exe — for Haswell+ Intel processors
stockfish_11_C0_x64_modern.exe — for ‘modern’ AMD and Intel processors. Use this with Ryzen chips.
stockfish_11_C0_x64.exe — for generic 64 bit CPUs.
stockfish_11_C0_x32.exe — for 32 bit CPUs. (May not work – untested. Let me know if it does for you!)
These files were compiled using MSYS and GCC 9.2.0 on a Windows 10 machine (either an i5-8250 or Ryzen 3700x). No warranty is made or implied with these engines – use at your own risk.
SF dev versions compiled under this setup work for normal analysis in ChessBase, Fritz, Blitzin, TarraschGUI, but do occasionally throw faults when used for automated analysis in Fritz, at least on one of my machines. Caveat emptor.
Virustotal scan for the .zip file: