Uncharted 4 Avx2 Fix Instant

AVX2 (Advanced Vector Extensions 2) is a set of CPU instructions used to improve performance for things like physics calculations and AI. Modern games often utilize these instructions to run more efficiently.

The problem arises because Uncharted 4: Legacy of Thieves Collection on PC was compiled to rely heavily on AVX2 instructions. Unlike some other games that include "fallback" code for older processors, Uncharted 4 attempts to execute these instructions immediately upon startup. If your CPU was released before 2013 (specifically Intel 4th Gen Haswell or older), your hardware cannot understand these instructions, leading to an instant crash.

The AVX2 fix demonstrates a replicable pattern for extending software lifespan: uncharted 4 avx2 fix

This case joins other preservation efforts (e.g., SSE2 fixes for older games on Pentium III).

The fix installs a global hook on __cpuid / __cpuidex. When the game queries AVX2 support (leaf 7, EBX bit 5), the hook returns 0, forcing the engine into a legacy SIMD path. Additionally, the hook masks OSXSAVE bits to prevent AVX2 activation. AVX2 (Advanced Vector Extensions 2) is a set

AVX2 (Advanced Vector Extensions 2) is a set of CPU instructions introduced by Intel with its Haswell architecture (2013) and later by AMD with Excavator (2015) and Ryzen (2017).

Games use AVX2 for:

Author: Technical Analysis Division, Game Preservation Society (fictional affiliation for paper purposes)
Date: April 2026

Game studios often compile with /arch:AVX2 in MSVC for vectorization and enable Intel IPP libraries that assume AVX2. Adding runtime dispatch increases QA complexity. Iron Galaxy likely prioritized performance for the majority of modern CPUs. The AVX2 fix demonstrates a replicable pattern for

Depending on your technical comfort level, there are three ways to bypass the AVX2 lockout. Warning: These are unofficial workarounds. Proceed at your own risk.

We diffed the original and patched game executables (binary diffing using Diaphora). Identified replaced AVX2 instructions were mapped to equivalent AVX or SSE sequences. CPUID interception via DLL injection was verified.