Windows 8 Irregular System Freezes without BSOD

[Sangheili Zealot]

Greetings,

My system (Win 8.1 64bit) freezes at random times.
The first time this happened was on 10/3/2015 9:53:45 PM (from Event Viewer: Kernel-Power Error).

Here's how it goes:

1. I do stuff at my computer (it only froze when I did multiple things at a time, like playing a game, skyping and listening to music)
2. My PC freezes and everything immediately stops (no audio continues to go on or something)
3. After about 10 seconds my PC instantly shuts down
4. After another 1 - 1.5 seconds it starts again automatically.

Some points where it froze:
- playing Dying Light, skyping (browser open, hamachi open etc.) <- twice in a row
- playing League of Legends, skyping, I shared my screen over skype to show something
- playing League of Legends, skyping (randomly at the end)

I also could induce it by just starting League of Legends and moving the camera. (was only for a short time)

Other things that I have found out (may also be coincidence):
- it only happened at evenings so far (probably after running the pc for a longer time)
- it only happened when the cpu was stressed out/multiple applications were running

Tomorrow when I start my PC I will try to induce it using skype screen sharing and running a game.

Screenshots of CPU-Z, Rammon and W7F-tool are attached to this post.

Edit #1: I just started a game of League of Legends and shared the screen and after ~3-5 seconds it froze.


Please help me solve this, it's very frustrating..

 

[Sangheili Zealot]

No crashes as of 14 October 2015.
I'll activate the antivirus again soon and see if it crashes.

 

[kemical]

Sounds good.. Hope all goes well but if not post back.