Quote Originally Posted by Sam_oslo View Post
With that description, probably it's related to your RAM/IMC, but some of these early BIOSes, a buggy one, can act that way too.
You could try to run a memtest, and if it passes, the try a little 1-hour Prime small FFT. In this way you can determine if it's the CPU/vCore or RAM. If both passes, look for BIOS update.
I just pulled a 2500k that I managed to get to 5Ghz @ 1.44v. So it's definitely not the memory. Just since I put the 2600k this started.