For anyone looking to purchase a hard drive upgrade for their Macbook pro Seagate Momentus 7200.4 ST9500420AS Purchased from: Newegg.com Capacity: 500GB Rotational Speed: 7200 RPM Cache: 16MB Form Factor: 2.5" Interface: SATA 3.0Gb/s Installed into: mid-2010 Macbook Pro 13" base model (2.4Ghz C2D) Speed I see no real difference between the stock 250GB and this one, but hey no difference isn't bad for the price point and the size. For raw stats, here is the AJA test results: Noise From reading around, this is a problem with some drives. This drive is louder than the stock drive but the fans in the back overpower it even at low temperatures. Vibration This drive does have a barely noticeable vibration when you place your hand over the bay, but I never really looked for vibration before installing it so its hard to compare. Suffice it to say it's not obnoxious and you can't notice it while typing.