Yes, it is. Of course it is. That's exactly why you shouldn't overclock unless you educate yourself CORRECTLY so that you know exactly what you are doing.
What is your CPU model, motherboard model, and what did you raise both the core voltage and the frequency TO?
So, are you saying that the system works, runs, will POST and boot, or no. Because in your first post you indicated that it won't boot and that you have a blinking LED error light. At only 1.3v you should not have caused any damage to anything.Cod will lag on 4k resolution now