Corsair
Corsair RM850x (2024)
$169.99
Released 2024
Best Power Supplies · head-to-head
A sourced, side-by-side comparison. be quiet! Pure Power 12 M 850W is cheaper at $134.9. Every spec and price links to its source.
Corsair
$169.99
Released 2024
be quiet!
$134.9Cheaper
Released 2023-02
On the specs we track, they're closely matched. The be quiet! Pure Power 12 M 850W is the cheaper at $134.9.
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✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.
| Spec | | |
|---|---|---|
| US price | $169.99 MSRP, black model | $134.9 MSRP (USD) |
| Brand | Corsair | be quiet! |
| Released | 2024 | 2023-02 |
| Wattage (W) | 850 | 850 |
| Efficiency rating | 80plus_gold | 80plus_gold |
| Modular | full | full |
| Atx version | ATX 3.1 | ATX 3.0 |
| Pcie 5 12vhpwr | Yes | Yes |
| Fan size (mm) | 140 | 120 |
| Warranty years | 10 | 10 |
| Release year | 2024 | 2023 |
Sources — Corsair RM850x (2024): corsair.com (verified 2026-06-19). be quiet! Pure Power 12 M 850W: bequiet.com (verified 2026-06-19).
Where the two actually differ on the specs we track (2 of 7). Matching specs are omitted.
Sourced tester consensus for each — the "what people who used it think" layer, not just specs.
Across 2 testing outlets, the Corsair RM850x (2024, ATX v3.1) tested as a capable, well-engineered 850W PSU. KitGuru rated it 9.0/10 after a week of testing, praising tight ripple suppression and solid load regulation across all rails, though it flagged the roughly £148/€160 price as expensive. Igor's Lab's lab measurements independently back up the strong build, recording Cybenetics Gold efficiency, a Cybenetics A noise rating, and a 10-year warranty, alongside confirmation that the unit meets the new ATX v3.1 standard. (2 sourced reviews, 2 lab-tested.)
Praised: Very capable, well-built PSU overall; Tight ripple suppression and good load/voltage regulation across all rails; Strong efficiency (Cybenetics Gold) and quiet operation (Cybenetics A noise rating), plus 10-year warranty and ATX v3.1 compliance.
Flagged: Relatively expensive (~£148 / ~€160).
No sourced tester review yet.