Should I defrag my external HD even if it said no need to defrag ?

I tried to do the defragment for my external HD today and it said there is no need to defrag now. I've been stocking up a lot of data in this HD, and it's been running a bit slow since I bought it 3 months ago. Can anyone guide me ? and should I do the disk error check as well ? if so, there are 2 items in the dialog box, should I check both of them ? The default setting is that both are unchecked. Thank you guys.

 

does the drive need defragging?

 

it said no in the dialog box.

 

Then you don't need to defrag the drive (according to Windows). You might get a little more speed out of the drive if you defrag.

 

there ya go

 

Usually external drives are not too affected by fragmentation because the interface (USB) is too slow and has high latency anyway. So even a fragmented HDD can keep up with it.

You might perceive it as slow, but it might not be. Try to benchmark it with HDTune, what's your average transfer rate?

 

I'm not sure about how much HDtune would give me, but the package states that it's 480mps. Correct me if it's the wrong information that I'm looking at.

 

Thats the speed USB 2.0 claims that it can get up to. It will never get close to that.

 

480mbs translates to 60MB/S. This is theoretical. Real life values are much lower and depend on the USB controller. Notebook USB controllers tend to be slower than ones found in desktops or on dedicated USB cards.

So in effect your limit is the interface not the HDD.

My external plugged into my notebook benchmarks at a consistant 20MB/S or a bit less.
Plugged into my desktop, it goes to 30MB/S.
Remove the HDD and plug it directly into a desktop thru an IDE cable its close to 50MB/S

So what I am trying to say is no matter how fragmented, its not going to slow the drive enough until it's slower than the interface