From a6d055d7e27ab3e29a42e8b94215102824760057 Mon Sep 17 00:00:00 2001
From: sscg13 <iamdumbybear1@gmail.com>
Date: Fri, 13 Feb 2026 12:54:51 -0800
Subject: [PATCH] Update NNUE architecture to SFNNv13 and net
 nn-5227780996d3.nnue

Since the introduction of Threat Inputs in SFNNv10 and its refinements, the
accumulator/L1 size has significantly decreased. This has made it more
computationally favorable to double the L2 size from 16 to 32.

Failed STC:
LLR: -2.98 (-2.94,2.94) <0.00,2.00>
Total: 189184 W: 49649 L: 49635 D: 89900
Ptnml(0-2): 881, 22479, 47812, 22585, 835
https://tests.stockfishchess.org/tests/view/69928ef7bfe62dc95a624d5c

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 37902 W: 9833 L: 9509 D: 18560
Ptnml(0-2): 35, 4074, 10408, 4400, 34
https://tests.stockfishchess.org/tests/view/69937936ff782f8eeef611e3

Passed VLTC SMP:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 20576 W: 5455 L: 5191 D: 9930
Ptnml(0-2): 6, 1837, 6338, 2101, 6
https://tests.stockfishchess.org/tests/view/6994df0586e4a32314116399

closes https://github.com/official-stockfish/Stockfish/pull/6619

bench: 2396996
---
 src/evaluate.h               | 2 +-
 src/nnue/nnue_architecture.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/evaluate.h b/src/evaluate.h
index 8a60ce238..df273f8ae 100644
--- a/src/evaluate.h
+++ b/src/evaluate.h
@@ -33,7 +33,7 @@ namespace Eval {
 // for the build process (profile-build and fishtest) to work. Do not change the
 // name of the macro or the location where this macro is defined, as it is used
 // in the Makefile/Fishtest.
-#define EvalFileDefaultNameBig "nn-7e1657811c6d.nnue"
+#define EvalFileDefaultNameBig "nn-5227780996d3.nnue"
 #define EvalFileDefaultNameSmall "nn-37f18f62d772.nnue"
 
 namespace NNUE {
diff --git a/src/nnue/nnue_architecture.h b/src/nnue/nnue_architecture.h
index 71fce9bd5..389c84bbd 100644
--- a/src/nnue/nnue_architecture.h
+++ b/src/nnue/nnue_architecture.h
@@ -41,7 +41,7 @@ using PSQFeatureSet    = Features::HalfKAv2_hm;
 
 // Number of input feature dimensions after conversion
 constexpr IndexType TransformedFeatureDimensionsBig = 1024;
-constexpr int       L2Big                           = 15;
+constexpr int       L2Big                           = 31;
 constexpr int       L3Big                           = 32;
 
 constexpr IndexType TransformedFeatureDimensionsSmall = 128;