I bought my MacBook with a stock 60GB HD - it was a Seagate Momentus 5400.2 (ST96812AS) - with a view to getting a larger HD myself and slotting it in. I did this a few days ago with a 120GB version of the same Momentus 5400.2 drive (ST9120821AS). I stuck with Seagate as the 60GB drive was near-silent and is advertised exactly as the 120GB I bought. Although the 120GB drive is working fine performance-wise, it makes a clunking noise randomly. Sometimes it could be every few seconds, sometimes every few minutes. It's quite loud and very annoying. My original drive didn't do this so I'm wondering if it's (120GB) faulty or if there's a way I can remedy it. I have sent an email to Seagate and am waiting to hear from them but what do you guys think? Does anyone with a MacBook have a 120GB Seagate in there? Does it clunk?