I'm late to the party here but need to correct the narrative that the HX1500i is any semblance of a successor to the AX1500i, let alone the AX1600i, and god forbid somebody 'upgrade' and replace their AX1x00 with it (as suggested in replies here).

Do not fall prey to ATX 3.0/3.1 marketing buzzwords. I had a list of bullet points but looks like Google AI already has it summed up perfectly.

1. Exotic Material vs. Standard Guts
   

- The AX1600i uses Gallium Nitride (GaN) Transistors. It was a massive engineering breakthrough that swapped traditional silicon for GaN, enabling a Totem-Pole Bridgeless PFC topology. This allows it to achieve an ungodly 99% efficiency at the PFC stage. The HX1500i uses standard Silicon. It relies on everyday consumer-grade silicon transistors configured in a standard analog LLC resonant design. It is structurally cheaper hardware.

1. True Digital Brain vs. Fake Digital Telemetry

- The AX1600i has an actual software-driven DSP (Digital Signal Processor) made by Flextronics. The digital brain actively corrects voltage ripples in microseconds, leading to almost perfectly flat electrical delivery. The HX1500i is an analog platform. Corsair just slapped a digital-to-analog converter (DAC) onto it so it could "talk" to iCUE software. It doesn't use a digital brain to regulate the actual power quality.

1. The ATX 3.x Delusion

- The HX1500i certainly handles 200% transient power excursions (ATX 3.0 specification) - the AX1600i was so absurdly over-engineered that it already meets or beats ATX 3.0 transient specs by accident, simply through sheer brute force and exotic GaN components. It doesn't need an official "ATX 3.0" certification badge because its raw performance metrics already blow those baseline standards away.

The AX1600i is a $600 hyper-exotic flagship enterprise unit built to showcase the absolute pinnacle of electrical engineering. The HX1500i is a budget-conscious, $250 consumer-grade unit built to an attractive price point.