Long time user, First time issue. 
  
Aida64 v 5.75.3900 
  
I7 6700/ Asus Maximus VIII water cooled. Overclocked to 4.5@ 1.296v 
  
At random times I will see ether PCH or VRM temp spike to over 200c than back to normal temps of 29c to 33c  temps idle. No other temps do this.  
  
Thanks, if more info. needed let me know.