Dev Builds » 20260829-0716

Use this dev build

NCM plays each Stockfish dev build 20,000 times against Stockfish 15. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds.

Summary

Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo
ncm-dbt-01 06:48:20 583573 3994 1804 302 1888 +137.4 ± 4.44 0 21 496 1437 43 +323.12 ± 15.28
ncm-dbt-02 06:47:43 591493 4006 1818 289 1899 +139.68 ± 4.3 0 15 482 1468 38 +333.62 ± 15.49
ncm-dbt-03 06:46:31 577997 4000 1824 272 1904 +142.25 ± 4.32 0 24 435 1506 35 +344.89 ± 16.35
ncm-dbt-04 06:46:31 567663 4000 1795 312 1893 +135.25 ± 4.37 0 16 522 1425 37 +317.52 ± 14.86
ncm-dbt-05 06:47:53 606190 4000 1847 293 1860 +142.46 ± 4.34 0 8 483 1456 53 +338.44 ± 15.43
20000 9088 1468 9444 +139.4 ± 1.95 0 84 2418 7292 206 +331.31 ± 6.91

Test Detail

ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN
484000 ncm-dbt-02 592029 6 2 0 4 +120.22 ± 109.7 0 0 1 2 0 +279.24 ± 576.89
483999 ncm-dbt-01 581236 494 221 32 241 +140.05 ± 13.36 0 2 64 171 10 +318.76 ± 42.94
483998 ncm-dbt-03 577315 500 220 30 250 +138.99 ± 12.7 0 5 54 187 4 +333.32 ± 47.06
483997 ncm-dbt-05 607604 500 224 40 236 +134.15 ± 12.47 0 1 70 173 6 +309.64 ± 40.79
483996 ncm-dbt-04 564487 500 229 41 230 +137.37 ± 12.76 0 3 62 179 6 +321.19 ± 43.77
483995 ncm-dbt-02 594541 500 235 35 230 +147.19 ± 12.14 0 1 55 187 7 +356.21 ± 46.49
483994 ncm-dbt-01 584411 500 227 41 232 +135.76 ± 13.39 0 6 58 180 6 +315.35 ± 45.33
483993 ncm-dbt-03 579868 500 224 36 240 +137.37 ± 12.36 0 3 60 183 4 +327.18 ± 44.54
483992 ncm-dbt-05 607786 500 237 31 232 +152.18 ± 12.31 0 1 51 189 9 +370.41 ± 48.42
483991 ncm-dbt-04 567997 500 224 45 231 +130.14 ± 13.52 0 5 68 170 7 +293.29 ± 41.75
483990 ncm-dbt-02 589924 500 218 35 247 +133.34 ± 11.88 0 3 62 184 1 +321.19 ± 43.77
483989 ncm-dbt-01 579289 500 230 39 231 +139.8 ± 11.62 0 0 63 183 4 +336.45 ± 43.03
483988 ncm-dbt-05 603859 500 233 30 237 +149.68 ± 11.32 0 0 52 193 5 +374.1 ± 47.75
483987 ncm-dbt-03 578753 500 230 25 245 +151.34 ± 11.69 0 2 46 197 5 +381.7 ± 51.25
483986 ncm-dbt-04 566612 500 222 39 239 +133.34 ± 11.67 0 3 61 186 0 +324.17 ± 44.15
483985 ncm-dbt-02 590653 500 227 36 237 +139.8 ± 11.62 0 0 63 183 4 +336.45 ± 43.03
483984 ncm-dbt-01 583279 500 217 29 254 +137.37 ± 12.36 0 3 60 183 4 +327.18 ± 44.54
483983 ncm-dbt-03 576660 500 225 37 238 +137.37 ± 12.15 0 2 62 182 4 +327.18 ± 43.69
483982 ncm-dbt-05 606110 500 231 35 234 +143.89 ± 11.87 0 2 54 190 4 +352.8 ± 47.05
483981 ncm-dbt-04 569151 500 224 41 235 +133.34 ± 12.09 0 1 69 176 4 +312.48 ± 41.11
483980 ncm-dbt-02 588600 500 225 45 230 +130.94 ± 12.37 0 3 67 177 3 +306.84 ± 41.99
483979 ncm-dbt-01 583028 500 221 46 233 +126.97 ± 12.85 0 6 65 177 2 +295.94 ± 42.75
483978 ncm-dbt-03 577356 500 226 35 239 +139.81 ± 12.26 0 4 54 189 3 +339.63 ± 47.1
483977 ncm-dbt-05 603410 500 232 34 234 +145.54 ± 12.01 0 0 59 184 7 +349.43 ± 44.59
483976 ncm-dbt-04 568355 500 218 37 245 +131.74 ± 12.14 0 0 74 171 5 +304.07 ± 39.39
483975 ncm-dbt-02 590438 500 222 37 241 +134.95 ± 12.24 0 3 62 182 3 +321.19 ± 43.77
483974 ncm-dbt-01 583279 500 231 33 236 +145.54 ± 12.43 0 2 55 186 7 +349.43 ± 46.59
483973 ncm-dbt-04 567363 500 225 42 233 +133.34 ± 12.49 0 1 71 172 6 +306.84 ± 40.47
483972 ncm-dbt-03 576864 500 237 38 225 +146.36 ± 11.96 0 4 46 197 3 +366.78 ± 51.18
483971 ncm-dbt-05 602650 500 228 41 231 +136.56 ± 11.76 0 0 67 179 4 +324.16 ± 41.61
483970 ncm-dbt-02 593629 500 225 38 237 +136.56 ± 12.59 0 3 62 180 5 +321.19 ± 43.77
483969 ncm-dbt-01 585717 500 234 41 225 +141.44 ± 11.77 0 1 59 186 4 +342.85 ± 44.76
483968 ncm-dbt-05 598083 500 228 43 229 +134.95 ± 12.64 0 1 70 172 7 +309.64 ± 40.79
483967 ncm-dbt-04 565272 500 233 34 233 +146.36 ± 11.52 0 0 56 189 5 +359.67 ± 45.87
483966 ncm-dbt-02 591642 500 231 39 230 +140.62 ± 12.44 0 2 60 182 6 +333.32 ± 44.47
483965 ncm-dbt-03 575720 500 229 29 242 +147.19 ± 12.57 0 3 51 189 7 +356.21 ± 48.54
483964 ncm-dbt-03 581444 500 233 42 225 +139.81 ± 12.05 0 1 62 182 5 +333.32 ± 43.57
483963 ncm-dbt-01 588345 500 223 41 236 +132.54 ± 12.52 0 1 72 171 6 +304.07 ± 40.16
483962 ncm-dbt-02 591986 500 233 24 243 +154.7 ± 11.94 0 0 50 191 9 +381.69 ± 48.77
483961 ncm-dbt-05 620023 500 234 39 227 +143.07 ± 13.54 0 3 60 176 11 +327.18 ± 44.54
483960 ncm-dbt-04 572074 500 220 33 247 +136.56 ± 12.39 0 3 61 182 4 +324.17 ± 44.15

Commit

Commit ID 8bc5caa2e4b1d4c189b1428e93158b10d3edb0b6
Author Timothy Herchen
Date 2026-08-29 07:16:46 UTC
Peel off one iteration of the halfka incremental update Passed STC https://tests.stockfishchess.org/tests/view/6a8ab17b08c0f6a39c9e79ae LLR: 2.96 (-2.94,2.94) <0.00,2.00> Total: 96192 W: 24637 L: 24264 D: 47291 Ptnml(0-2): 136, 9961, 27552, 10288, 159 Passed avx2 STC: https://tests.stockfishchess.org/tests/view/6a8cd16708c0f6a39c9e7e59 LLR: 2.94 (-2.94,2.94) <0.00,2.00> Total: 61024 W: 15789 L: 15457 D: 29778 Ptnml(0-2): 108, 6534, 16905, 6848, 117 Failed avx512icl STC: https://tests.stockfishchess.org/tests/view/6a8cd14d08c0f6a39c9e7e57 LLR: -2.96 (-2.94,2.94) <0.00,2.00> Total: 90368 W: 22968 L: 23088 D: 44312 Ptnml(0-2): 132, 9707, 25587, 9665, 93 Context: https://github.com/official-stockfish/Stockfish/pull/7051#issuecomment-5285531017 Credit to bobbypaper for inspiring the idea. Gated to AVX2 because it seems neutral at best on other architectures. Locally, despite the avx512icl failure: Result of 500 runs base (...kfish.master) = 1907788 +/- 1384 test (./stockfish ) = 1930017 +/- 1426 diff = +22230 +/- 1978 speedup = +0.0117 P(speedup > 0) = 1.0000 closes https://github.com/official-stockfish/Stockfish/pull/7096 No functional change
Copyright 2011–2026 Next Chess Move LLC