XMP is made by intel, and it is designed, from what I read, to overclock the RAM. I have ddr4 2666 RAM and that is what my CPU can support up to, nothing else higher. If XMP is activated from the start, and it overclocks the RAM, will it void the warranty of the CPU?
While some XMP profiles would technically be considered to be a form of overclocking, using these profiles is not going to void your warranty. From the standpoint of the DRAM itself, you are not overclocking it; it is designed to support its highest XMP Profile (or that profile wouldn't be there). The issue is the higher clock speed of the memory buses and whether operating these buses at these speeds is going to disaffect the processor. In fact, with the exception of a very slight increase in the overall temperature of the processor, these higher bus speeds are not going to disaffect the processor.
Had a chat yesterday with a tech (I guess) from Intel and he was going down a list of questions and one question came up was have I enable the XMP on my mother board. After I said "Yes", he said that voided the warranty. Is this true? I have never (even tho I have though about OC), it scared me and I stop. However, I heard XMP was okay.