Corsair RM1000x SHIFT (2025) vs Corsair RMx Series RM1000x Fully Modular Power Supply

Researched, not hands-on tested.How we review ›

all judged against power supplies at a similar price

The Corsair RM1000x SHIFT (2025) scores 7.8/10 overall, ahead of the Corsair RMx Series RM1000x Fully Modular Power Supply at 7.7/10.

The Corsair RM1000x SHIFT (2025) leads on noise.

The Corsair RMx Series RM1000x Fully Modular Power Supply leads on efficiency.

They score the same on quality and protections, cabling and connectors and warranty.

Corsair RM1000x SHIFT (2025)

7.8/10verdict: buy

The RM1000x SHIFT (2025) suits builders putting together a high-end gaming or workstation PC with a current NVIDIA card. It offers 1000W, a native 12V-2x6 cable and a side-mounted modular connector layout. It fits people who want a quiet, long-warranty supply and have case space for the side connectors.

Typically about £129.99 in the UK when we researched itCheck price at Amazon UK

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Corsair RMx Series RM1000x Fully Modular Power Supply

7.7/10verdict: buy

The Corsair RM1000x suits builders putting a high-power graphics card into a new ATX system. It also fits drive-heavy workstations and homelab machines that need many SATA connectors. It is a fully modular 1000W unit with a 10-year warranty and a native 12V-2x6 connector.

Typically about £130 in the UK when we researched itCheck price at Amazon UK

Affiliate link. As an Amazon Associate I earn from qualifying purchases. Details

Scores, criterion by criterion

Criterion	Weight	Corsair RM1000x SHIFT (2025)	Corsair RMx Series RM1000x Fully Modular Power Supply
Quality and protections	30%	7/10	7/10
Efficiency	20%	7/10	8/10
Cabling and connectors	20%	8/10	8/10
Noise	15%	8/10	6/10
Warranty	15%	10/10	10/10
Overall		7.8/10	7.7/10

Specifications

Spec	Corsair RM1000x SHIFT (2025)	Corsair RMx Series RM1000x Fully Modular Power Supply
Rated output (W)	1000W combined (+12V 83.3A, 1000W total)	1000W continuous
Efficiency	Cybenetics Gold	Measured Cybenetics Platinum: 89-91% at 115V, 91-93% at 230V (Hardware Busters)
Form factor	ATX, ATX 3.1 certified, PCIe 5.1 compliant	ATX, 160x150x86 mm (Corsair); 150x85x160 mm (Hardware Busters)
Cabling	Fully modular	Fully modular, Type-4 cables
GPU power	One native 12V-2x6 cable; PCIe 8-pin counts differ by source; SATA 12 (Tech2Geek) or 16 (Corsair white SKU page)	1x PCIe 12V-2x6 (12+4), 4x PCIe 8-pin (6+2), 2x EPS 8-pin, 12x SATA, 6x PATA
Fan size and zero-fan mode	140mm fluid dynamic bearing fan, model NR140HP, with Zero RPM mode	1x 140mm fluid dynamic bearing fan with Zero RPM mode and manual override knob
Warranty (years)	10 years	10 years

Strengths and weaknesses

Corsair RM1000x SHIFT (2025)

+ Quiet running with Zero RPM fan mode
+ Native 12V-2x6 cable and fully modular design
+ 10-year warranty
− LTT Labs lists under-voltage protection as absent
− Side connectors need 30mm clearance to the side panel

Skip it if:

Builders whose case has less than 30mm between the PSU and side panel.
Buyers who want under-voltage protection on the spec sheet.
Anyone with a low-power or always-on system that doesn't need 1000W.

Read the full Corsair RM1000x SHIFT (2025) review ›

Corsair RMx Series RM1000x Fully Modular Power Supply

+ 10-year warranty
+ Native 12V-2x6 plus four PCIe 8-pin and 12 SATA
+ Platinum-level efficiency measured on 230V
− Light-load efficiency is modest, about 74% at 20W
− Some owners report scratchy fan noise near full speed
− Some owners say the fan runs at full speed at desktop

Skip it if:

Buyers building a low-power always-on box who want high efficiency at very light loads
Buyers who need an utterly silent system and are bothered by reports of fan noise
Buyers with a small chassis that cannot take a roughly 160 mm deep ATX unit

Read the full Corsair RMx Series RM1000x Fully Modular Power Supply review ›

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