PC parts / Power supplies
CORSAIRPower supply
RM850x SHIFT (2025)
Released November 2025.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Corsair press release dated November 4, 2025, Milpitas. It says the RMx SHIFT PSUs are available immediately in 750W, 850W and 1000W. Spanish reviews are dated the same day and Hardware Busters follows on November 16, 2025. Last checked 16 October 2026.
- Power
- 850W
- Efficiency
- Cybenetics Platinum
- Modular cables
- Fully modular
- ATX version
- ATX 3.1
52 of 66 fields known.
At a glance
Average noise
Lower than 89% of other power supplies. Lower is better.
Hold-up time
Higher than 87% of other power supplies.
General
- Model numbers
- CP-9020299-NA, CP-9020299-EU, CP-9020299-UK1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026SKU CP-9020299-NA. The power table prints model RPS0221 and part no. 75-006527, which are not stored as model numbers.7Retailer pageamazon.com/dp/B0FPGD7XDKRead 15 October 2026Item details: Model Number CP-9020299-NA.8Retailer pagewebshop.netip.dk/corsair-rm850x-shift-80-gold/cat-p/c/p1006311000Read 15 October 2026SKU CP-9020299-EU.9Retailer pagescan.co.uk/products/850w-corsair-rm850x-shift-fully-modular-cybenetics-gold-pcie-51-single-rail-708a-140mm-fan-aRead 15 October 2026Scan lists CP-9020299-UK.
- GTIN / EAN
- 840440484981, 840440484974, 8400066794487Retailer pageamazon.com/dp/B0FPGD7XDKRead 15 October 2026Item details: UPC 840440484981 and Mfr Part Number CP-9020299-NA. The check digit is valid.8Retailer pagewebshop.netip.dk/corsair-rm850x-shift-80-gold/cat-p/c/p1006311000Read 15 October 2026SKU CP-9020299-EU with EAN 0840440484974. Multitronic and DCS list the same code. Komputronik and Datafox also list 840006677284 for the same part number, which has a valid check digit too. The code that matches the US UPC prefix is stored.9Retailer pagescan.co.uk/products/850w-corsair-rm850x-shift-fully-modular-cybenetics-gold-pcie-51-single-rail-708a-140mm-fan-aRead 15 October 2026Scan lists manufacturer code CP-9020299-UK with GTIN 840006679448. The check digit is valid. This is the only source for the UK code.
- Announced
- 4 November 20253Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Press release dated November 4, 2025.
- Predecessor
- Not available
- Successor
- Not available
- Launch price (US)
- Not available
- Markets
- Not available
- ATX version
- ATX 3.11Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Overview: ATX 3.1-certified and PCIe 5.1 compliant. Tech Specs: ATX12V Version 3.1.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Meeting ATX 3.1 and PCIe 5.1 standards.
- PCIe CEM version
- PCIe 5.11Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Overview: ATX 3.1-certified and PCIe 5.1 compliant.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Meeting ATX 3.1 and PCIe 5.1 standards.
- Modular cables
- Fully modular1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Overview: Fully modular with Type-5 connectors.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Fully modular, so builders can use only the cables they need.
- Built by (OEM)
- Great Wall5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026DUT Information: OEM/ODM Great Wall. Parts description: Manufacturer (OEM) Great Wall.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Technical specifications: Manufacturer (OEM) Great Wall.
Power
- Rated continuous power
- 850W1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Continuous Power W 850 Watts and Total Power 850W.
- Full power rated up to
- Not available
- 12V rail design
- Single rail5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Power Specifications: one +12V column with 70.8 A and 850 W.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Technical specifications: Number of 12V rails 1.
- +12V max current
- 70.8A1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Power table: +12V 70.8A, 850W.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x power table, model RPS0221, part no. 75-006527: +12V 70.8A, 850W.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Power Specifications table: +12V 70.8 A, 850 W.
- +12V max power
- 850W1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Power table: +12V 70.8A with 850W listed beside the row. The Cybenetics report also prints 850 W for +12V.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x power table: +12V 70.8A, 850W.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Power Specifications table: +12V 850 W.
- +3.3V and +5V combined power
- 120W1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Power table: +3.3V 20A and +5V 20A with one 120W cell. The page layout does not tie the 120W to one rail. The Cybenetics report and Hardware Busters print it as the combined +3.3V and +5V power.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x power table: +3.3V 20A, +5V 20A and one 120W cell.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Power Specifications table: one merged 120 W cell for 3.3V and 5V, 20 A each.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Technical specifications: Power 5V + 3.3V 120W.
- +5V standby current
- 3A1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Power table: +5VSB 3A, 15W.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x power table: +5Vsb 3A, 15W.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Power Specifications table: 5VSB 3 A, 15 W.
- AC input voltage
- Lowest100Highest240V1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Power table: AC input 100V-240V, input current 10A-5A, 47Hz-63Hz.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x power table: AC input 100V-240V, input current 10A-5A, 47Hz-63Hz.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Manufacturer-provided information: 100-240 Vrms, 5-10 A, 47-63 Hz.
- Alternative low power mode (ALPM)
- Yes1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Modern Standby Yes. The Cybenetics report ticks ALPM compatible.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Temperature and Compliance Info: ALPM (Alternative Low Power Mode) compatible, checked. ATX v3.1 PSU Power Excursion is checked.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Technical specifications: Alternative Low Power Mode support Yes.
Certifications
- 80 PLUS rating
- Not available
- Cybenetics efficiency at 115V
- Cybenetics Platinum5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Report 25PS2879, lab ID CR85002879, sample serial A9H1D518401FMC, received Jun 13, 2025, tested Jul 7, 2025, issued Jul 10, 2025. The model name is RM850x Shift (ATX v3.1). The Cybenetics database shows ETA Platinum at 115V. Corsair advertises Cybenetics Gold without a voltage, and Hardware Busters says Corsair used a lower badge on purpose. The report wins.
- Cybenetics efficiency at 230V
- Cybenetics Platinum5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026The Cybenetics database shows ETA Platinum at 230V.
Measured
- Average efficiency at 115V (measured)
- 90.009%5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Average over more than 1450 load combinations at 115V, ambient 28-32 C. Hardware Busters prints 90.080% for 115V and 92.076% for 230V, which differ slightly from the report page.
- Average efficiency at 230V (measured)
- 91.794%5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Average over more than 1450 load combinations at 230V.
- Light-load efficiency at 115V (measured)
- 72.66%5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Efficiency at 2% load (more than 500 W unit) at 115V.
- Average power factor at 115V (measured)
- 0.9925Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Average over more than 1450 load combinations at 115V. At 230V it is 0.966.
- Average noise at 115V (measured)
- 10.65dB(A)5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Average over more than 1450 load combinations at 115V, ambient 28-32 C, Bruel and Kjaer 2270 G4 sound analyzer. The 230V average is 10.97 dBA. The fan stays at 0 rpm up to 50% load.
- Noise at full load at 115V (measured)
- 32.8dB(A)5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Typical load tests at 115V, 100% load row: 32.8 dB(A) at 1064 rpm fan speed, ambient about 30 C. At 230V it is 32.2 dB(A) at 1037 rpm.
- Standby power with no load at 115V (measured)
- 0.0405W5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Standby power consumption at 115V with no load on +5VSB: 0.0405 W. At 230V it is 0.0818 W.
- Hold-up time (measured)
- 24.5ms5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Hold-Up Time and PWR_OK Signal: hold-up time 24.50 ms, AC loss to PWR_OK 19.70 ms, PWR_OK inactive to DC loss 4.80 ms, at maximum continuous load. The report names no input voltage.
- 12V ripple at full load (measured)
- 20.97mV5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Non-accredited. 12V ripple at full load at 115V. At 230V it is 22.45 mV.
- 12V load regulation (measured)
- 0.57%5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Non-accredited. 12V load regulation at 115V. At 230V it is 0.57%.
Cables and connectors
- Cables
Connector Connectors Cables Length to first plug (mm) Wire gauge Rated power (W) ATX 24-pin (20+4) 1 1 610 16-20AWG Not available CPU 8-pin (EPS, 4+4) 2 2 650 18AWG Not available PCIe 8-pin (6+2) 4 3 650 18AWG Not available 12V-2x6 1 1 650 Not available 600 SATA power 9 3 500 18AWG Not available 4-pin Molex 4 1 450 18AWG Not available Source1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Cable listing: 1 ATX 24-pin 610 mm, 2 EPS 4+4-pin 650 mm, 2 PCIe 8-pin (6+2-pin) 650 mm, 1 90-degree 12V-2x6 to 600W 12V-2x6 (12+4-pin) 650 mm, 1 600W 90-degree 12V-2x6 to 2x 8-pin PCIe (6+2-pin) cable with 2 plugs 650 mm, 3 SATA cables with 3 plugs each (500 mm to the first plug, 100 mm spacing, 700 mm total) and 1 PATA cable with 4 plugs (450 mm to the first plug, 100 mm spacing, 750 mm total). All lengths have a tolerance of 10 mm. PATA plugs are the 4-pin Molex plugs. The 12V-2x6 to 2x 8-pin cable is stored as a PCIe 8-pin cable with 2 plugs. It and the 12V-2x6 cable both plug into the native 12V-2x6 socket of the PSU, as Hardware Busters says the modular panel has one native 12V-2x6 header. The Cybenetics report and Hardware Busters list the 2x 8-pin cable as 2 cables with 2 connectors, which does not match Corsair's listing. Gauges come from the Cybenetics report.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026Included cables for the RM850x, with the SATA count stated for the 850W: 1x ATX 24-pin 610 mm, 2x EPS 4+4-pin 650 mm, 2x PCIe 8-pin 650 mm, 1x 90-degree 12V-2x6 to 2x 8-pin PCIe 650 mm, 1x 90-degree 12V-2x6 to 600W 12V-2x6 650 mm, 3x SATA, 1x PATA.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Cables and Connectors table: ATX 24 pin 610 mm 16-20AWG, 2 x 4+4 pin ATX12V 650 mm 18AWG, 2 x 6+2 pin PCIe 650 mm 18AWG, 2 x 2x 6+2 pin PCIe 650 mm 18AWG, 12+2 pin PCIe 650 mm (600W) 16-24AWG, 3 SATA cables with 9 plugs in total 18AWG and 1 Molex cable with 4 plugs 18AWG, no in-cable capacitors. The 16-24AWG range of the 12V-2x6 cable includes the sideband wires, so no gauge is stored for it. The 18AWG gauge of the PCIe cables is stored for the 2x 8-pin cable too.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Cables page: the modular panel has eleven sockets including one native 12V-2x6 header, and all cables are debossed PVC. Review date November 16, 2025.- CPU (EPS) connectors
- 2
- PCIe 8-pin connectors
- 4
- 16-pin GPU connectors
- 1
- SATA power connectors
- 9
- 4-pin Molex connectors
- 4
- Cable style
- Embossed or debossed flat1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Cable listing: Debossed cable type for every cable. Tech Specs: Cable Type Type 5. Stored as embossed, which covers debossed jackets.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Improved debossed-PVC cables with low-profile combs.
Fan
- Fan size
- 140mm1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Fan Size MM 140mm.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026A quiet 140mm fluid dynamic bearing fan.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026DUT Information: 140mm Fluid Dynamic Bearing Fan (NR140HP).
- Fan bearing
- Fluid dynamic (FDB)1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Fan Bearing Technology FDB. Overview: 140mm Fluid Dynamic Bearing fan.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026A quiet 140mm fluid dynamic bearing fan.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Parts description: Corsair NR140HP, 140mm, 12V, 0.33A, Fluid Dynamic Bearing Fan.
- Fan mode
- Semi-passive1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Overview: Zero RPM Mode for near-silent operation at lower loads.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Zero RPM mode: the fan switches off entirely at low and medium loads. A rear-mounted knob adjusts fan speed.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026DUT Information: Semi-Passive Operation checked (selectable). The typical load table shows the fan at 0 rpm from 10% to 50% load.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Technical specifications: Semi-Passive Operation yes (selectable). Corsair's guide says the fan speed knob sets the speed once the fan starts and does not turn Zero RPM mode off, so no fan mode switch is stored.
- Fan mode switch
- Not available
Protection and parts
- Protections
- Over-current (OCP), Over-voltage (OVP), Under-voltage (UVP), Over-power (OPP), Over-temperature (OTP), Short-circuit (SCP), No-load (NLO), Surge and inrush (SIP)2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026Protection section for the series: OVP on 12V, 5V and 3.3V, OCP on 3.3V, 5V and 12V, OTP, SCP and OPP. UVP, NLO and SIP come from the Hardware Busters protection tests.5Measurementcybenetics.com/evaluations/psus/2879Read 15 October 2026Protection Features (Manufacturer): OPP, +12V OCP, OTP, SCP, surge protection and inrush protection ticked, fan failure protection not present.6Reviewhwbusters.com/psus/corsair-rm850x-shift-atx-v3-1-psu-reviewRead 15 October 2026Protection Features page: OCP on 12V, 5V, 3.3V and 5VSB, OPP, OTP, SCP, UVP (90V full load and 80V no damage), NLO and SIP (surge MOV, inrush NTC and bypass relay) all shown. Fan failure protection is not present.
- All-Japanese capacitors
- Yes1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Overview: 105 C-rated, 100% Japanese electrolytic capacitors. The Cybenetics parts list also shows polymer capacitors from FPCAP, which the claim does not cover.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026105 C-rated 100% Japanese capacitors.
Monitoring and lighting
We could not find any of these 4 fields. Show them
- Software monitoring
- Not available
- Software
- Not available
- Built-in power display
- Not available
- RGB lighting
- Not available
Dimensions and weight
Front and side, drawn to scale.
- Dimensions
- Width150Height86Depth160mm(5.9 × 3.4 × 6.3 in)1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Dimensions 160mm x 150mm x 86mm with no axis names. The quick start guide gives length 160 mm, width 150 mm and height 86 mm. Depth is 160 mm.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026RM850x specifications: 160mm length, 150mm width, 86mm height.
In the box
We could not find any of these 1 fields. Show them
- In the box
- Not available
Links
- Product page
- www.corsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-na1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026
- Spec sheet
- Not available
- Manual
- www.corsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generation2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026Quick start guide of the RMx SHIFT Series 2nd generation. It covers the 750W, 850W and 1000W models. The page also keeps no separate PDF.
- EPREL registration number
- Not available
Warranty
- Manufacturer warranty (source market)
- 10years1Maker product pagecorsair.com/us/en/p/psu/cp-9020299-na/rm850x-shift-fully-modular-atx-power-supply-cp-9020299-naRead 15 October 2026Tech Specs: Warranty 10 Year and the Overview says 10-year warranty. The page is the US shop.2Owner's manualcorsair.com/us/en/explorer/diy-builder/power-supply-units/corsair-rmx-shift-series-2nd-generationRead 15 October 2026CORSAIR RMx SHIFT Series 2nd Gen PSUs have a 10-year warranty.3Press releasecorsair.com/newsroom/press-release/corsair-launches-second-generation-rmx-shift-psus-with-updated-cables-and-12v-2x6-gpu-supportRead 15 October 2026Each unit includes a ten-year warranty.
Compare with
Pick a power supply to see both side by side. Differences are marked yellow.
Variants
Each variant lists only what differs from the specs above.
| Model number | GTIN | Launch price (EU) |
|---|---|---|
| CP-9020299-NA | 840440484981 | Not available |
| CP-9020299-EU | 840440484974 | €169.9 |
| CP-9020299-UK | 840006679448 | Not available |
Sources
We read 9 sources for this power supply. The numbers match the markers in the sheet.
- Measurementcybenetics.com/evaluations/psus/2879
- Retailer pageamazon.com/dp/B0FPGD7XDK
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