Unexplained Hard System Crashes

[Cjohnson]

Help! My PC keeps crashing. I've had games crash from overclocking/instability before. However, I've never had crashes like this. Yesterday I was a few hours into playing the new expansion in Destiny 2 and my entire PC instantly turned off as if I pulled the power cord out of the socket. Since then, it's been happening more frequently. Today it crashed only about 20 minutes in. Usually, it runs perfectly at 4k getting anywhere from 130 to 165 fps in 4k max settings.

 

My only guess is that I may be overloading my power supply? Any ideas would be appreciated

 

PC Specs:

-GPU: Powercolor RedDevil rx 7900xt (overclocked to 2750 MHz memory, +15% power limit, 2.8 - 3.2 GHz GPU, adjusted fan curve and temps 58 to 80 C)

-CPU: r7 5800x3d (not overclocked)

-16 Gb ddr4 3600 MHz

-Motherboard: MSI MAG B550 Gaming

-CPU Cooler: Arctic liquid freezer 240 AIO

-Case: Hyte Y40

-PSU: Corsair RM850x (the PSU is about 5 years old)

-Storage: Mvme, and SATA SSD