SeaSonic PRIME Platinum 850W vs SeaSonic S12III 450W

A side-by-side spec comparison of the SeaSonic PRIME Platinum 850W and the SeaSonic S12III 450W. We line up every specification and score the ones that matter most in this category — weighted, not a raw count of specs won — to reach an overall verdict so you can decide which power supply is right for your build.

Side-by-side specification comparison of SeaSonic PRIME Platinum 850W and SeaSonic S12III 450W.
Specification	SeaSonic PRIME Platinum 850W No price data Winner	SeaSonic S12III 450W No price data
Modular	full	non-modular
Wattage	850W	450W
Efficiency	80+ Platinum	80+ Bronze
Form Factor	ATX	ATX

Winner: SeaSonic PRIME Platinum 850W — driven by Efficiency (80+ Platinum), Wattage (850W), Modular (full)

SeaSonic PRIME Platinum 850W

performance points

SeaSonic S12III 450W

performance points

Winner is scored by weighting the specs that matter most in this category (not a raw count of specs won).

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