corsair rm1000x

Hello all. MY PC setup is : MB : ASUS ROG Crosshair X870E Hero (new) RAM : 2x48 GB RAM DDR5 6000MHz (new) PSU : Corsair RM1000x ( 3 months old ) SSD : Samsung 990 Pro - 6 months old (on RMA now), Samsung 980 (as replacement, 3 weeks old for now) GPU : ASUS Prime RTX 5080 (new) CPU Cooler ...

So bought a RM1000x for a ryzen build and tested the supply through a cheap power supply tester , The PG (power good) is blinking at 90ms and other rails are under spec. I tried plugging this through my UPS which is a 1000VA APC and that instantly went into bypass mode and sounded the alarms. Is...