Running modern Python TTS toolchains on non-AVX2 CPUs

Notes from getting F5-TTS, StyleTTS2, kokoro/Misaki, and whisper.cpp to work

on an AMD Phenom II X6 1090T (2010 K10/Family-10h architecture).

The CPU has SSE/SSE2/SSE3/SSE4a, plus CX16/POPCNT/LAHF — but no SSE4.1, no

SSE4.2, no AVX, no AVX2, no FMA, no F16C . That puts it below the modern

x86-64-v2 baseline. A growing share of binary Python wheels in the AI

ecosystem assume v2 or v3, so they SIGILL or SIGFPE at import. This is a

ground-truth list of what we hit and what worked.

Quick triage

If your CPU is below x86-64-v2 (in particular, missing SSE4.1 ), expect:

pyarrow static-init pinsrq SIGILL on import

numpy 2.x wheel SIGILL on import (numpy 1.26.4 still has a fallback path)

torch 2.10+ wheel SIGFPE in torch._dynamo on import

pandas modern wheels SIGILL on tokenisation

monotonic_align and other Cython extensions: build-from-source SIGILL

DataLoader subprocess workers SIGFPE re-importing torch

If your CPU is x86-64-v2 (Nehalem ~2008 or…