Question System sometimes boot sometimes not

[dageramit]

i left my system left on overnight. in morning it was off. i tried starting and it didn't. Motherboard was showing red light 00 code. i tried 2-3 time and then it started fine but was slower than usual.
same thing happens 2-3 days then it completely shutdown and was showing 00 all the time.
00 is cpu code. but if that is fried then how it started once in a while. i am not sure if it's board or the cpu. can anyone help so that i buy the right part.

Cpu: i5-4690k
Mobo: Asrock z97 extreme 6

 

[Lutfij]

We will need more information. List your full system's specs like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:

Include the age of your PSU(apart from the make and model of the unit).