Question Help with Random Shutdowns?

[TribeFan85]

I first had this problem about a week ago, and ever since, my PC shuts down completely about once a day (hard shutdown no bluescreen). Mostly this occurs while gaming, but at least once it has happened while simply on the web (not under heavy load). Until two days ago, I had my PC hardwired to my router, and when the shutdowns occurred, it would also shut down the router. Since switching to WiFi, obviously this does not happen anymore, but I feel like that detail may be important. Specs are:

CPU: i5-6600k @ 4.4 gHz
Cooler: Corsair H100
MoBo: Asus Z170 Pro Gaming
PSU: EVGA Supernova 750G
Memory: 2x8GB Geil EVO X
GPU: EVGA 1070SC
OS: Windows 10

Given that not every time this has happened has been under load, I feel it is safe to rule out the CPU. My best guess is either the PSU or MoBo, but I'm not sure how to start eliminating potential causes to find the real issue. Any suggestions or advice would be much appreciated. Thanks!

 

[jojesa]

A computer should not be in any way powering off a router.
It could be that there was a power outage (power flicker) and both devices went off.

If there wasn't any power interruption, then there is something wrong with your PSU, case or motherboard grounding.