Question Strange Issue, PSU-Related?

[Not Batman]

Over the past few days, my PC has spontaneously shut down. Nothing has shown in the error logs, and generally it has just powered off silently. A few times this has coincided exactly with replacing cables (swapping an HDMI cable to another machine that I was testing, replacing a broken Ethernet cable, plugging in/removing USB devices). It has also fully shut down when I accidentally bumped (but did not disconnect) the power cord.

This morning, when I woke the PC from sleep, it ran for roughly a minute before it spontaneously shut down, this time with some disturbingly static-like crackling from inside the case. I've opened it up, but there's no burning smell or any signs of damage at a glance (I'll be taking it apart soon to check for damage). Preliminary research suggests this may be PSU-related, but I wanted to be sure.

FYI: PSU is a Corsair CX750M, circa 2014.

 

[kerangovender]

Most computers today are designed to turn off automatically if any of its inner components overheat.

If you find that the fan in the power supply is not working correctly or at all, and the power supply is very hot to the touch, you may need to replace the power supply. An overheating power supply, due to a malfunctioning fan, can cause a computer to shut off unexpectedly. Continuing to use the faulty power supply can result in damage to the computer and should be replaced immediately.

Start by verifying the fan on the power supply is working by examining the back of the computer. The fan should be moving quickly and smoothly. All other fans in the computer require you to open your case to inspect them. Once you have access to the inside of your machine, examine the processor (heat sink), video card, and case fansIf you have heard any abnormal noises coming from your computer, such as a high squealing sound, it could be an indication of a fan malfunction.

 

[Not Batman]

Thanks. I've verified that all fans are functional - PSU, case, CPU & GPU. No odd noises. No indication that the PSU is overheating at this time. I've done a check of the motherboard as well, there does not appear to be any physical damage.

Since you brought up overheating, I'm going to check the thermal paste for the CPU as well.

Have not been able to pinpoint the static crackling noise from inside the case though, and that's got me a little worried. As does that odd correlation between the cable connection/disconnection and the shutdowns.