Tom's Hardware Verdict
Corsair's AX1000 is one of the best 1kW power supplies available. If you want the highest possible performance matched with quiet operation, don't hesitate to make it the centerpiece of your next build (provided the price doesn't scare you off).
Pros
- +
80 PLUS Titanium & Cybenetics ETA-A+ efficiency
- +
Solid build quality
- +
Excellent results through our benchmark suite
- +
Fully modular
- +
8x PCIe & 2x EPS connectors
- +
Sleeved cables
- +
Selectable semi-passive mode
- +
Ten-year warranty
Cons
- -
Expensive
- -
EPS connectors should use 16AWG wires
- -
Short distance between the peripheral connectors
- -
OCP triggering points on the minor rails should be set lower
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Features and Specifications
Corsair's AX1000, along with the 80 PLUS Platinum- and Titanium-rated Seasonic Prime models, are currently the best 1kW PSUs that money can buy. The recently refreshed AX family consists of high-performance 1000W and 850W models, which are ideal for enthusiasts with power-hungry hardware they want to overclock. Both PSUs are based on the amazing Seasonic Prime Titanium platform. And although this is an analog design, it still sets an example for digital platforms to follow.
The AX1000 is not an inexpensive power supply; it mostly caters to builders who view their PSU purchase as an investment. Shouldn't we all think that way, though? After all, your PSU is the heart of your PC.
At least for the time being, there is no 1000W model in the AXi family. The AX1000 plays alone, followed by the lower-rated HX1000 and HX1000i in Corsair's portfolio.
On the other hand, the AX850 looks similar to the AX860i. It lacks a digital interface, but offers a better efficiency classification, partially justifying a higher price.
Specifications
| Manufacturer (OEM) | Seasonic |
| Max. DC Output | 1000W |
| Efficiency | 80 PLUS Titanium, ETA-A+ (91-94%) |
| Noise | LAMBDA-A (20-25 dB[A]) |
| Modular | ✓ (Fully) |
| Intel C6/C7 Power State Support | ✓ |
| Operating Temperature (Continuous Full Load) | 0 - 50°C |
| Over-Voltage Protection | ✓ |
| Under-Voltage Protection | ✓ |
| Over-Power Protection | ✓ |
| Over-Current (+12V) Protection | ✓ |
| Over-Temperature Protection | ✓ |
| Short Circuit Protection | ✓ |
| Surge Protection | ✓ |
| Inrush Current Protection | ✓ |
| Fan Failure Protection | ✗ |
| No Load Operation | ✓ |
| Cooling | 135mm fluid dynamic bearing fan (HA13525M12F-Z) |
| Semi-Passive Operation | ✓ (selectable) |
| Dimensions (W x H x D) | 152 x 87 x 172mm |
| Weight | 2.06 kg (4.54 lb) |
| Form Factor | ATX12V v2.4, EPS 2.92 |
| Warranty | 10 years |
Power Specifications
| Rail | 3.3V | 5V | 12V | 5VSB | -12V | |
|---|---|---|---|---|---|---|
| Max. Power | Amps | 25 | 25 | 83 | 3 | 0.3 |
| Watts | 125 | 996 | 15 | 3.6 | ||
| Total Max. Power (W) | 1000 |
Cables & Connectors
| Modular Cables | ||||
|---|---|---|---|---|
| Description | Cable Count | Connector Count (Total) | Gauge | In Cable Capacitors |
| ATX connector 20+4 pin (610mm) | 1 | 1 | 16-20AWG | Yes |
| 4+4 pin EPS12V (650mm) | 2 | 2 | 18AWG | Yes |
| 6+2 pin PCIe (670mm+100mm) | 4 | 8 | 16-18AWG | Yes |
| SATA (460mm+110mm+110mm+110mm) | 4 | 16 | 18AWG | No |
| Four-pin Molex (450mm+100mm+100mm+100mm) | 2 | 8 | 18AWG | No |
| FDD Adapter (110mm) | 1 | 1 | 22AWG | No |
| AC Power Cord (1400mm) | 1 | 1 | 14AWG | - |
This is a fully modular PSU with fairly long cables. With that said, we'd expect the distance between peripheral connectors (especially the four-pin Molex ones) to be greater. Moreover, the EPS connectors should utilize thicker wires for lower voltage drops under high loads.
The number of SATA connectors is amazingly high, and it is nice to get so many four-pin Molex connectors as well. There's even a bundled Berg adapter for enthusiasts who still need a FDD connector.
Component Analysis
| General Data | |
|---|---|
| Manufacturer (OEM) | Seasonic |
| Platform Model | Prime |
| Primary Side | |
| Transient Filter | 6x Y caps, 3x X caps, 2x CM chokes, 1x MOV |
| Inrush Protection | NTC thermistor & relay |
| Bridge Rectifier(s) | 2x Vishay LVB2560 (600V, 25A @ 105°C) |
| APFC MOSFETs | 2x Infineon IPP60C7099 (650V, 14A @ 100°C, 0.099Ω) |
| APFC Boost Diode | 1x STPSC10H065D (600V, 10A @ 135°C) |
| Hold-up Cap(s) | 1x Hitachi (400V, 470uF, 2000h @ 105°C, HU) 1x Hitachi (400V, 820uF, 2000h @ 105°C, HU) |
| Main Switchers | 4x Infineon IPP50R140CP (550V, 15A @ 100°C, 0.14Ω) |
| Drivers For Main Switchers | 2x Silicon Labs Si8230BD |
| APFC Controller | ON Semiconductor NPC1654 |
| Switching Controller | Champion CM6901 |
| Topology | Primary side: Full-bridge & LLC resonant converter Secondary side: Synchronous rectification & DC-DC converters |
| Secondary Side | |
| +12V MOSFETs | 6x Nexperia PSMN1R0-40YLD (40V, 280A @ 25°C, 1.4 mΩ) |
| 5V & 3.3V | DC-DC Converters: 6x Infineon BSC0906NS PWM Controller: APW7159 |
| Filtering Capacitors | Electrolytics: Nippon Chemi-Con (105°C, W, KZE, KYB), Nippon Chemi-Con (4000-10,000h @ 105°C, KY), Rubycon (3-6000h @ 105°C, YXG), Nichicon (5000-6000h @ 105°C, HV) Polymers: FPCAP, Nippon Chemi-Con |
| Supervisor IC | Weltrend WT7527V (OVP, UVP, OCP, SCP, PG ) & AS393M |
| Fan Model | Hong Hua HA13525M12F-Z (135mm, 12V, 0.36A, 1800 RPM, fluid dynamic bearing) |
| 5VSB Circuit | |
| Buck Converter | Leadtrend LD7750R |
| Rectifiers | STMicroelectronics STU6N65K3 (650V, 3A @ 100°C, 1.3Ω) Infineon BSC0906NS (30V, 40A @ 100°C, 4.5 mΩ) |
| -12V Circuit | |
| Buck Converter | Lite-On LSP5523 (3A max output current ) |
The AX1000's platform is the same one used in Seasonic's top-notch Seasonic Prime Titanium (and Platinum) models. It is built using high-quality components from companies like Vishay, Infineon, and Nexperia. In addition to its Japanese electrolytic caps, the secondary side also features a number of polymer capacitors from FPCAP and Chemi-Con.
A fluid dynamic bearing-based cooling fan serves up a longer useful life than lower-cost alternatives. And even though the -12V rail goes unutilized these days, we're still glad to see a proper rectifier used for it instead of a plain diode.
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