Hardware Spec Index

Zephyra PW-6421 Ultra 550W 80 PLUS Bronze ATX Power Supply

Power Supplies · Zephyra · SKU PW6421-ULTRA · Released 2021 · Updated 2026-10-24

Key facts

Benchmark index729 (Power Supplies scale)
Category rank#39,390
Street price$39
Power550 W (rated)
Performance per dollar18.69
Released2021

Specifications

BrandZephyra
ModelZephyra PW-6421 Ultra
Rated output550 W continuous
Efficiency80 PLUS Bronze (85% at 50% load, 115 V)
StandardATX 12V 2.53
GPU powerNone
PCIe 8-pin2×
Form factorATX
ModularityNon-modular
Fan140 mm fluid dynamic bearing, zero-RPM mode
Hold-up time≥ 16 ms
ProtectionsOCP, OVP, UVP, OPP, OTP, SCP
Warranty5 years

Related guides

80 PLUS Efficiency Ratings ExplainedATX 3.1 Power Supplies and the 12V-2x6 Connector

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Cite this page: Hardware Spec Index, “Zephyra PW-6421 Ultra 550W 80 PLUS Bronze ATX Power Supply”, https://vextor7.com/item/19214726 (accessed 2026-10-24).