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answer: direct
beat: tech
source: 1 article · updated: October 17, 2026
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Why can two same-seed training runs differ?

A seed controls some sources of randomness, but training also depends on hardware, software, parallelism and the order of numerical operations. Floating-point addition is not perfectly associative, so different reduction orders can produce slightly different values that later updates may amplify.

Answered in

Why Two Identical AI Training Runs Can Still Disagree

Bitwise reproducibility requires matching the full training setup and operation order, not merely reusing the same random seed.

Crashtech Editorial October 17, 2026 Tech

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