Reading around on practically every forum on the internet, it seems like 2500k owners are hitting 4.5ghz overclock at around 1.3 Vcore. Unfortunately, my CPU needs over 1.36 to reach a stable 4.5ghz OC. Did I make a mistake in some settings? Or could it be just the specific chip I have is not as efficient? Is a .06 difference in voltage compared to the common voltages i see online a normal occurrence?
You have an average clocker. I wouldn't worry to much about it. Some chips just need a little more juice that's all I also found that with Sandy bridge Gigabyte boards seem to require more voltage when overclocking compared to Asus boards. My Asus Z68 board would take my 2600k to 4.5ghz on 1.31V full load. My Gigabyte board requires 1.355V for the same flipping overclock on the same chip. But that's just my observation as well as a few others I talk with. I would say 1.35-1.36 is the norm for a 4.5ghz OC.