We found a refurbished Corsair AX860i at NewEgg for $99.99 which cost us $139.99 Canadian. The AX860i is platinum rated so its extremely efficient. Corsair offers a ten year warranty for the AX860i suggesting they are close to invincible.
We have purchased a single PSU for the studio for general use. We are considering perhaps more of them in 2019 as we desire to improve the efficiency of all of our machines. We have several older 850W power supplies and the AX860i is ideal as an upgrade replacement.
The AX860i has been available for several years and they are generally well regarded. The RMA rate is < 2% which is excellent. One feature we like is that the series all come with a pair of EPS12V cables for dual slot class motherboards. We first noticed the dual EPS12V on some Intel Z170 motherboards.
The 8-pack of PCI Express cables means even the worst power pig video cards with triple cable connectors are not a problem.
Cables galore for fans and disks are also included making this PSU a real useful asset.
This level of power is suitable for one or two extreme video cards. Today video cards are powerful enough to handle 4K panels reducing the need for dual video cards. Still all power supplies are more efficient at partial loads so we can take advantage of excess capacity for features like the zero fan mode for low noise.
The Corsair USB cable is not necessary as HWinfo etc can all read the motherboard sensors just fine.
We have read of some users who have experienced a boot loop cycle of their machines. We speculate that the 2×12 cable is most likely the problem. Faults that occur after time suggest thermal effects on cables may be at issue.
We suspect that the cables should be removed and reattached to eliminate a bad connection.