This is a special match between Stockfish and McCain. The previous Stockfish vs. Clones tests showed that McCain was always below Stockfish in rank. My confidence with the strength tests was shaken when McCain was the clear winner in the recent similar test conducted with the author of McCain. To eliminate the unnecessary rating noise, I decided to make a one on one death match between the two engines. Instead of 100 rounds, I made a longer 800 rounds which is the result of using the 400 positions root opening moves at 2 ply depth with both engines repeating the same position alternately. Effectively, all the first 2 moves combination are used which include many seldom seen moves like 1. a3 a6. This also fit with my aim of collecting of games which had all these 400 root positions covered.
The tournament conditions are as follows:
Time control: 1 minute base + 1 second increment
Opening: all 400 root positions at 2 ply depth
Resign score: 200cp
Draw score: 20cp after 40 moves
Concurrency: 10 threads
Rounds: 800 with alternating colors
The Stockfish 19042419 compile was drawn from abrok.eu and the McCain X3 was a compiled version done by Corbit. Default parameters were used without touching any, no native opening books and no endgame tablebases. The tournament manager used was cutechess-cli 1.1 linux version.
The result showed that Stockfish is marginally stronger with a 6.14 ELO difference in which the previous results. My confidence in my previous testing results is strengthened. If there is no agreement with the results done with other testers, then so be it. There are many other factors that will make the results inconsistent. This is just my personal test.
|1||Stockfish 19042419 x64||6.14||800||51.75||24.75||54.00||21.25|
|2||McCain X3 x64||-6.14||800||48.25||21.25||54.00||24.75|
Download the match PGN games