The Corsair RM1000x is a 1000W fully modular, ATX form factor, ATX 3.1 power supply. It offers a single hybrid fan mode and was launched in 2024 with a MSRP of $189.99 USD.
This model (CP-9020271-NA) has been updated to be compliant with the newest ATX 3.1 version, supporting PCIe 5.1, and the inclusion of a 12V-2x6 cable ensures it can handle high-wattage GPUs, providing up to 600W. The 2021 version (CP-9020201-NA) can still be found through various online retailers, it is not ATX 3.1 but is sold under the same name — RM1000x.
As of August 2024, Corsair has moved away from CLEAResult 80PLUS certifications to Cybenetics, and as such this refresh of the RM1000x is only Cybenetics Platinum-certified.
We are recommending the Corsair RM1000X for its high efficiency at low loads, and good overall performance across all tests.
WHAT YOU NEED TO KNOW
THE GOOD
- Cables
The included cables are very flexible and individually stranded which can be organized with the included cable combs.
- Efficiency
It delivered particularly high efficiencies at low 2% loads.
- Performance
Delivered good overall performance across most tests with only a few very minor missed test points.
THE BAD
- Nothing at the time of writing
THE REST
- Overall
The RM1000x maintained good results across all tests. It is recommended for its high efficiency at low loads, and general performance. Labs tested the 2024 model which is updated to reflect ATX 3.1 standards.
*This website uses affiliate links. Purchases made through these links may provide compensation to Linus Media Group.
The Corsair RM1000x is an ATX form factor power supply. In the Box, it includes minimal accessories, providing only the essential mounting screws, zip ties, and cable combs. The power supply was secured in the box with cardboard inserts, certainly more sustainable than the typical foam. There may be concern that the cardboard won't provide sufficient cushion and support for the product, but our unit arrived without damage and we've seen no evidence of this packaging being insufficient.
The included cables are very flexible and individually stranded which can be organized with the included cable combs. As aforementioned, Corsair has switched from 80PLUS certifications to Cybenetics, and as such this power supply is Cybenetics Platinum-certified. Cybenetics calculates their certifications differently, for more information on Cybenetics certifications, please visit their explanation page.
This unit is equipped with a 140 mm Fluid Dynamic Bearing which should provide sufficient cooling. On the Corsair product page it specifies that the Operating Temperature is up to 50°C, though we cannot verify this through testing.
1 of 3
Front of the box.
1 of 2
Power input side of the PSU.
Top of the PSU displaying the fan.
Bottom of the PSU displaying the specifications.
| +12 V | +5 V | +3.3 V | +5 Vsb | -12 V | |
|---|---|---|---|---|---|
| CURRENT | 83.3 A | 20 A | 20 A | 3 A | N/A |
| WATTAGE | 1000 W | 150 W | 15 W | N/A | |
| 1000 W | |||||
Please note that the above ratings are manufacturer advertised specifications.
The RM1000x SHIFT offers a single hybrid fan mode, allowing the fan to remain off under light loads for quieter operating — a feature Corsair refers to as “Zero RPM” mode. In place of an on/off fan mode button on the rear of the power supply, Corsair has opted for a manual fan override knob to increase the fan speed and airflow.
The power supply is backed by a 10-year warranty.
- Zero RPM Fan Mode: Eliminate fan noise completely at low to medium loads.
- Manual Fan Override Knob Mode: Override the Zero RPM Mode profile to increase fan speed and airflow.
The RM1000x demonstrated solid overall performance across most tests, closely mirroring the RMx Shift variant but with slight improvements in certain areas. During load regulation testing, the 12V rail exhibited a voltage drop of 0.161V at full output power. Voltage ripple was generally within expected ranges, except for the 5V rail, which registered unusually low ripple values. Under full load, peak-to-peak ripple measured 32mV on the 12V rail, 12mV on the 5V rail, and 25mV on the 3.3V rail.
In power excursion testing, the unit performed consistently well, though a few minor deviations were noted at the 0.1ms excursions at both 0°C and 40°C. The voltage momentarily dropped to 11.172V and 11.186V, respectively — slightly below ATX specifications but unlikely to cause stability issues.
The RM1000x does not have a -12V rail therefore there are no results for this rail.
1 of 6
The RM1000x carries a Cybenetics Platinum certification, which, while assessed differently from 80 PLUS ratings, places its efficiency between low Platinum and high Gold 80PLUS levels. Its efficiency at low loads was particularly strong, achieving excellent performance even at just 2% load.
Brownout resilience was also commendable, with the unit maintaining stable operation for 18ms at 115V input and 17ms at 230V. Over Current Protection engaged consistently between 130% and 140% of rated capacity, with the exception of the 5Vsb rail, which exhibited minor inconsistencies — though its low power output makes this a negligible concern. Over Power Protection activated at a maximum of 131% of the rated load, with the 12V rail sustaining up to 108A, or 130% of its rating, aligning with expectations for a high-performance power supply in this class.