I bought his used off Craigslist for $1075 (Guy works at Apple, and can get a new MacBook for cheap with his 25% discount, so he sold it to me for a nice low price.) , and it as fine and beautiful except a dent on the back. It won't void my warranty, will it? Nothings wrong with it, but I figured if my GPU ever failed, or something happened, that they might deny me or something for accidental damage?