That must have been one bad batch. MY HX850 has run various top-end CPU's & GPU's, including SLI & Crossfire configs (when that was fashionable), daily for the past 11-years without issue. My two old 5870's must have pulled 500-600W by themselves.your lucky
We had 70 Servers running with Corsair HX850 running at 400W 24/7 inside a 20C A/C evironment (no downtime other than reboots)
- 2 years - 10 died
- 3 years - 30 died
- 5 years - 30 died
the only bad thing to happen to them was a few power cuts, but NOt great stats, decent but not great.
The only components that have ever failed me were a Powercolor HD4850 and several hard disks. The Powercolor failure was most-probably caused by me pencil-modding and overclocking the nuts out of it. It set an air-cooled MHz WR at the time.