Question: I am thinking of buying an external hard drive (NOT ONLINE) so what units do you recommend?
It needs 250GB or 320GB of storage. Also, how does the RPM of 5400 and 7200 affect the performance of the hard drive? Will there be a considerable difference in the speed of copying and opening files? I need it to support fast transfer times. I’ve read about some hard drives supporting max speeds of 480mbps, and that is fine with me. That is a USB 2 right? I think USB 3 hard drives with max speeds of 5gbps will be too expensive. But please, the price does not matter now since I do not have the money.

I am quite interested in the “Samsung 320GB SATA2 16MB 7200RPM Hard Disk Drive” and I need to know, what does the 16MB stand for? Is it the copying speed? If so, it is slow, and I’d consider it less.

Answer:

Answer by Toad
The 16 MB refers to the hard drive cache and this is a standard value. I wouldn’t go less than this though. There is a noticable difference between 5400 and 7200rpm so the hard drive you mentioned should be a good choice.

You mentioned needing fast transfer times. USB 3.0 is slightly more expensive but it’s also 10x faster which is significant. In addition to the drive you would also need the USB 3.0 card for your computer (assuming it’s a desktop). If you went with USB 3.0 you’d be looking at maybe an extra $ 30 – $ 50.

To compare:

Theoretical fastest possible time to transfer 10 GB:

USB 2.0: 2 minutes 45 seconds
USB 3.0: 16 seconds

The actual transfer time would end up being a bit slower than those values but the difference is obvious.