The Corsair AX1600i is an ATX standard power supply for personal computers. The MSRP is $499.99.

The 80 PLUS program starts looking obsolete in the context of advanced PSUs like the Corsair AX1600i. Even the organization’s highest rating (Platinum) cannot fully describe the potential of modern digital platforms. The competitive market today has motivated designs to make power supplies so incredibly efficient that it has reduced power plant requirements dramatically.

  • CP-9020087-NA
  • AX1600i
  • +5V@30A, +3.3V@30A, +12V@133.3A, -12V@0.8A, +5VSB@3.5A
  • 100 – 240 V 50/60 Hz
  • IOC C19 power cable
  • Corsair NR140P fan
  • 80 Plus Titanium
  • 10 year warranty

The Corsair AX1600i represents the finest quality of engineering possible for a personal computer power supply. Corsair has built a great reputation for delivering power supplies that do not disappoint.

1600W of Ultimate Power: Delivers 1600W of continuous, ultra-stable, 80 PLUS Titanium efficiency power. Top Tier Components: 100% 105°C Japanese capacitors, top-specification internal components and digital design deliver over 94% efficiency. The Only Consumer PSU with Gallium Nitride Transistors: Totem-pole PFC Gallium Nitride (GaN) transistors for superior efficiency in a smaller formfactor.

Corsair obviously puts a lot of resources into power supplies. The main reason is that while there are lots of chassis and other hardware products, Corsair has managed to make their power supplies the a powerful brand.

AX1600i rear connections


  • 1 x ATX (2×12 pin) (20+4)
  • 2 x EPS/ATX12V (8-pin) (4+4)
  • 10 x PCIe (8-pin) (6+2)
  • 4 x SATA (2 SATA)
  • 12 x SATA (4 SATA)
  • 9 x Peripheral (4-pin)
  • 2 x Floppy Adapter (4-pin)
  • 1 x USB (9-pin)

The AX1600i uses Corsair type 4 cables. The type 3 EPS12V and PCIe cables are interchangeable but the type 4 2×12 has additional sense lines which means the type 3 motherboard cable has to be swapped out. The sense lines are part of the revised ATX specifications. ATX standards are intended to maximize backwards compatibility. The 2×12 cable is keyed differently to prevent the wrong cable being used.

The AX1600i does not have a conventional PFC circuit. Instead a digital bridge-less converter similar to the AX1500i. In theory, classic APFC designs top out at 96% efficiency and the Totem-Pole Bridgeless PFC design that Corsair is using could reach up to 99%.

Corsair CP-9020087-NA ATX Power Supply
AC Input: 100V – 240V DC Output +3.3V +5V +12V -12V +5Vsb
Current: 8A Max Load 30A 30A 133.3A 0.8A 3.5A
Frequency: 50Hz – 60Hz Maximum Combined Wattage 150W 1600W 9.6W 17.5W
Total Maximum Power: 850W

The only real weakness is with the 5V standby efficiency. The HX1600i running the USB for a charger is < 70% efficient. The minor rails are overkill, reminding us of a previous era when most system components relied on 5V instead of the 12V rail. 5V today is mostly used by the USB ports which need a few amps for charging mobile devices etc. Looking at 3.3V it was showing 0.0 Amperes of current in an AM4 machine showings 3.3V’s days are numbered.

Synchronous converters are also common but not one with sixteen MOSFETs for the 12V line alone. The 5V and 3.3V lines are generated via additional DC to DC converters. The secondary side electrolytic capacitors are all provided by Nippon Chemi-Con. A slight cost savings will be seen once 3.3V is finally deprecated but the circuity remains for legacy requirements.

The Gallium Nitride (GaN) parts are smaller, lighter, and significantly more efficient than their silicon-based counterparts. Their use allowed Flextronics (and ultimately Corsair) to design a platform that combines better overall performance and higher output into a smaller chassis.  GaN parts are more expensive than their silicon-based counterparts but the final product’s cost was partially offset by the reduction in size and cooling requirements, allowing Corsair to maintain the price of the AX1600i at relatively reasonable levels.

No question that the AX1500i is a great PSU but the design of the AX1600i is categorically better. Better across the board with bigger capacitors and GaN semiconductors. The Totem Pole regulator design has been refined over time to be incredibly effective. Reaching 80 Plus platinum is tough standard to reach but Corsair has reached it with the AX1600i.

Stress testing the AX1600i with the carbon pile resulted in the breaker popping before the PSU shut down. Clearly all available grid power is converted to the PC with no reserves. The power factor is so good as to be almost perfect at 99.7%. The voltage deviation is less than 0.15V on the 12V circuit at idle vs loaded hard. 5V was also unphased by loads.

The assembly of the AX1600i is very well done. The components in the AX1600i are intended to handle the 133A of power draw for demanding workstation use, For gaming the AX1600i is a tad excessive but the best PSU does have bragging rights.


When installed in a contemporary PC with an elite graphics card the AX1600i is still 92%-93% efficient at idle. This means savings over time compared to older less efficient model power supplies. While saving 4% may not look like much it does add up over time.

The previous HX1000i is a respectable PSU and it served the studio for several years. The HX1000i is platinum rated while the AX1600i is titanium rated. Both carry a 10 year warranty which gives peace of mind.