Question PC randomly shutting off

Jul 14, 2020
I built my computer a few months ago. It has started to randomly shut off around once a week with no discernible pattern except that it's under light gaming loads, which is all I use it for. Sometimes it will turn back on by itself immediately. Most recently, it would not power on for 2 minutes or so. I have carefully monitored my temperatures since building it. It has shut off 4 times within 3-4 weeks. I'll bullet point info for brevity:

  • CPU sits under 60c most often, and 71 max during Cinebench. GPU sits in 50s during light loads, and max 70 during heavy loads. MOBO and other temps look under 40c.
  • Nothing in the system is overclocked beyond factory. XMP profile is on to utilize the 3600mhz ram.
  • The 3.3, 5, 12 Voltages look okay as far as I can tell. However, HWiNFO is telling me my power reporting minimum is reaching 81%, indicated in red, which is the only marker that something may off in the system. During Cinebench, the number looked more normal at 95%.
  • Ran memory diagnostics
  • Tested whether it was the surge protector
  • Looked for loose cables
-No other electronics lose power
-Drivers are up to date
-Using Ryzen balanced power plan

Hardware specs:
-Fractal Meshify C
-EVGA Supernova G3 650w 80+ Gold
-MSI B450 Tomahawk Max
-Ryzen 3600x
-Arctic Freezer 34 eSports Duo
-Asus RTX 2070 Super Dual EVO OC
-Intel 660p m.2 NVME 1tb
-G.Skill Ripjaws 16gb DDR4 3600
-Arctic F12 PWM case fans with aggressive temperature curve

I'm assuming at this point that either the power supply or Mobo is to blame. Does anyone have any troubleshooting thoughts?