CPU warranty info. (need help)

Hey guys,

I just wanted to ask how warranty applies to overclocked CPU's. I am starting to think about OC'ing my new CPU that i am going to get, but I am worried about the CPU breaking 6 months down the line or whatever. If I send the broken OC'ed CPU back to the shop, will this impact my warrenty and how could they tell that I OC'ed my CPU?

BTW I live in England if that helps somehow.

Ty for any help:D