Question PC randomly crashes, freezes and losing display signal during non intensive/idle situations ?


Apr 16, 2015
So in the last 6 months or so I started experiencing random crashes (blue screen), freezes and sometimes losing display signal on monitor. When losing signal non of my monitors works and only after force restart I am able to get my display to work. (there is no issue with the monitors I tested it with 3 different ones).
The most absurd thing about it is that it almost never happens during heavy workload or gaming. It happens almost always when I do very light stuff like talking on discord with some light softwares.
It also happens when the pc is idle. And by idle I mean the pc is on and not in sleep or anything. I just leave my room for an hour or two and when I return the display is off or the pc completely frozen.

Also I feel my pc doesn't perform as good as it should.
  1. Copying files from and to SSD from HDD and vice versa is slow for an SSD.
  2. It seems I don't get the most of my system even tho its old. It should be better then what I get.
What I tried so far is as follows:
Memetest86 (I did like 3 phases)
Stress test of CPU (Prime95)
Stress test of GPU (Furmark)

No issues and it make sense considering all crashes happen during non intensive tasks or any tasks at all.

My PC hardware is as follows:
Motherboard: Asus P8Z77-V LK2
CPU: Intel i7 3770
Ram: 16GB ddr3 1600MHz (not sure what brand)
GPU: GTX 1070 8GB MSI Gaming X
Soundcard: Creative Sound Blaster Z
SSD (Bootdrive): Samsung Evo 860 1TB
SSD 2nd: Kingston A400 480Gb
HDD: Seagate Barracuda 2TB
HDD 2nd: Hitachi (not sure about model but some very old HDD) 1TB
There are some other external HDD storage that I connect from time to time and they are staying connected for a week or 2 at a time.
OS: Windows 10