Disk Rotational Speed? Portable+Desktop?

I was looking at both portable and desktop hard drives and noticed that there is typically a difference in their rotational speeds (5400 vs 7200).

What does this mean and will it give a noticeable benefit?

Higher rotational speeds usually translate into lower latency, and higher data transfer rates.

The downside is they use more energy, create more heat, and are sometimes louder.

In practice you probably won't notice the difference.

Ok. Thanks Joe. So I probably wouldn't notice the difference in transfer speed between 5400 and 7200.

Are there any advantages/disadvantages of getting a desktop HD over a portable HD? I don't intend to put it inside the PC.

Desktop HDs are cheaper, and arguably more reliable. Downside is that they're bigger (duh), and if you're going to use it as an external drive then your external enclosure will need a power cable of it's own. External 2.5" drives are normally powered just by USB alone.

I've used both speed hdd's and haven't seen any big difference. Like has already been stated, there is a lower latency with the faster speed. I don't think most people would ever notice the difference between the two speeds. A big difference you would see day to day would be if you compared SSD against a platter hhd.

So I presume that the only important spec to look out for, in terms of speed, is the Data Transfer Rate.

Why are desktop drives bigger anyway, is the internal hard drive not the same?

Playdo said:

Why are desktop drives bigger anyway, is the internal hard drive not the same?

Click to expand...

Whenever you make something smaller (especially something with moving parts) the tolerances by which those parts are made become smaller meaning the manufacturing costs go up as does the possibility of defect. Desktops hard drives are bigger because portability isn't an issue, so they make them bigger because it costs less to do so.

Ok. I thought that the size of the internal hard drive would be the same for both a desktop and a portable hard drive.

Sorry, I thought you meant desktop vs laptop hard drives. External (portable) hard drives are just a standard desktop or laptop hard drive in an enclosure. They come in both 2.5" and 3.5" sizes, but the 2.5" ones are more common, which would be the ones with laptop hard drives in them.

I see. So most portable drives will contain a 2.5" laptop drive inside, whereas most external desktop drives will contain a 3.5" internal drive inside. I've got it.

Sorry, there still seems to be a bit of misinterpretation here. An external drive and portable drive are the same thing. You can get them in both sizes.

I was referring to an External Desktop Drive and a Portable Drive like the ones below. The Desktop is always larger than the Portable (both external drives).

http://www.amazon.co.uk/Western-Dig...1_1?s=computers&ie=UTF8&qid=1299090276&sr=1-1

http://www.amazon.co.uk/Western-Dig...1_6?s=computers&ie=UTF8&qid=1299090316&sr=1-6

The small portable drives are the ones that connect using only a USB cable, and utilize a 2.5" hard drive. The portable hard drives are small because people prefer to have a smaller means of storage that can also connect easily. The 2.5" portable drives also have a much larger capacity than any flash drive you could buy.

As you realized, the 2.5" hard drives are the ones which go into a laptop because of space requirements. Also, the 2.5" hard drives are almost exactly like a larger 3.5" hard drive, except that they are smaller due to miniaturization of all the parts used.

As PohTayToez said, the parts are miniaturized. This is made possible in large part because of much tighter tolerances between parts. Though it's also due to the modern ability to make parts MUCH smaller than we've ever been able to do. However, this also means that the smaller 2.5" hard drives are more susceptible to damage from being roughed around, or drops, etc.....

The larger desktop external hard drives are a 3.5". This is the size most commonly found in desktop computers and also desktop external hard drive enclosures. They can hold about the same amount or a little more than the 2.5" hard drive.

The benefit to the larger 3.5" hard drive is that the manufacturers do not have to try and shrink everything down so small. This makes the 3.5" drives easier to produce and that means lower cost of manufacturing, and a lower cost for you! Also some 3.5" drives also even incorporate design extras such as a heatsink into their casing to help dissipate any heat generated during use. Manufacturers can incorporate things like heatsinks because the 3.5" drives are larger and are usually installed/used in places where there is the room for the "extras".

The 3.5" drives typically require both a data connection as well as a power connection as they require more power than a smaller 2.5" does. The desktop external 3.5" drives are more commonly used for major backups. They are also used for long term storage, or anything really large you need stored but don't want taking up space on your C: drive.

For instance I have both a 2.5" external and a 3.5" external drive. My 3.5" is for my backups, and other large folders/files I don't want taking up large amounts of space on my C: drive. I use the 2.5 for storage/transfer of files/folders for easy access when I'm on the road.