How do you measure the size of the hard drive?

I'm trying to figure out if my hard drive is an 5.25" or 3.5" hard drive.

It's dimensions are 1 in x 4 in x 5.7 in (HxWxD), but that doesn't seem to tell me anything.

The model is a Samsung SP0401N...

Do you measure across, diagonally, or length-wise?

Here's a pic:



Thanks!

 

hint, the hard drive is the disk inside, so if you can measure corner to corner on a round disk, good look to you. i am just going to scan a dvd disk and hard drive disk side by side for you.brb

 

its 3.5"..........

 

we have a winner

and no it aint black, it is highly polished steal, that reflects the scanner light back so precise that it blinds the scanner

 

Very nice.. you must have pulled out the disk or something

Thanks for the answers, I see how you do it now.

 

The size of the platters are 3.5" and this is the size of the HDD. There are 3 common sizes:
The First: for desktops 3.5"
The Second: Laptops 2.5"
The Third: Certain Sony Viao have 1.8"

Then there are three types the SCSI, IDE & SATA (serial ATA).
Your HDD with that Model id an IDE HDD.

 

i think its 3.5

 

3.5" and here is your proof !

http://www.labx.com/v2/spiderdealer2/vistaSearchDetails.cfm?LVid=3678946

Thanks Samantha for the scan , but did u break your HD to scan it ?