Cpu running slow or something else?

[Kaip888]

Pc Specs-

GPU: gtx 970     CPU: Intel Core i5-4690k Ram: 16gb 2400hz Motherboard: Asus z97-a

When I play cs:go and skype my cs:go will crash and all of my programs seem to stop working, so I have to restart my computer. It only seems to happen when I'm skyping. My cpu usage is always around 97% when I'm doing this and it randomly crashes. Even without skype my cpu usage isn't much lower (80-95%). I'm not sure if it's my cpu slowing down or if there's else. This has been occurring in the past few months, but wasn't happening for the first year I built my computer. My pc is 1 1/4 year old.

[Megah3rtz]

Check for virus. 

[OliverKunnington]

I had a friend that all his games only run on his CPU instead of running on the GPU, is the GPU in idle state when you game?

[FrowningHippo]

Is the CPU usage always around 80 - 90 % usage or when playing the game? 

What kind of CPU do you have? (Press Windowsflag + R and type "Systeminfo")

What tasks use what kind of percentage of the CPU?  (Please post a screenshot of the task manager under those loads to see in a general view how the load is distributed)