So I upgraded my MBP to a 320GB 7200 from the stock 200. Normal HD worked fine, just wanted more space and a faster HD. Now the older HD won't work, not detected or spinning at all. Wasn't used at all, just sat in my desk in a 2.5" HD case. I know I can put it back in the MBP and take it to apple, I was just hoping I could bring in the HD and call it good. Only reason I am thinking this is that replacing the HD doesn't void the warranty and I need my MBP. I doubt they will be able to, but I am hoping.