This is what I've sent to fractal with no response after a few weeks. I tore both of the CM psu's apart and saw it was cooked looking at the large inductor(torroid) to the first FET/mosfet area. I'm not an electronics person but saw it was a bit browned there and smelled a bit blue smoky.  Read a bit further down to see how the evga supply died. This is a mystery at this point. I just don't want any more to die as these are customer machines in a fairly high demand application. They just don't want servers at this point. Thanks for reading.
 
Dear tech support,
I'm writing to discuss and investigate a problem we've have twice on two separate machines.
Both were built by the same independent builder. They are no longer in existence, pandemic.
But the machines were very similar. 
msi b450 a pro max
coolermaster 650 or 750 psu
ryzen 5 something, not sure but can find out
r6 case, not super sure, no fan grill on the side, covered PSU shroud all the way, 3 case fans. push button panel removals
fractal fan controller r-r-fdn-smarthub (jd0092-01D) (9 fan hub)
plugged into the pump header (is this the problem)
 
both machines killed their psu, one was 2 years old another was about 3 years old. 
one had it's psu replaced (evga 850 gold something) have a receipt if needed. this died in 5 days and blew the rooms 20 amp breaker when being reset. This machine needed a new MOBO, processor was still good. new PSU and it works, all the old hardware minus the PSU and MOBO work. booted into windows like it never happened.
 
both had a raid card and 4 hdd's tied in. spinny 1tb drives WD blues
2 sticks of ram, not sure what slots or setup, but can look further if needed
 
 
Can you think of what may have caused this. Is it a fan hub problem. Plugged into the wrong port. Something MOBO related. I'm guessing it's ones of those two things. Or PSU. But i doubt it as one died in 5 days. While they both ran about 2 years. The fans on both machines, controller or not. Would ramp up and down, while cpu idled. Maybe MOBO. Should I send this to MSI as well?
 

I definitely understand we void the warranty. I tore the CM's apart too but didn't see what failed. It was very interesting that they lasted so long. They were in different locations. One of them was in a residential area, not remote location. Other was remote and at a dead end road.
We were not interesting in getting an RMA, more just a see if anyone else has had a similar problem or light bulb moment. Or to save other's some heartburn.