Question HDD dimensions ?

[Lynval]

Hi,

I have a Dell Optiplex Mini Tower 7010 SFF with a 1.0 TB Hard Drive.

When I check the Websites , the Hard Drive is listed as 3.5-inch.

However, when I measure it, it measures 4.0-inches.

I don't understand.

 

[USAFRet]

Hi,

I have a Dell Optiplex Mini Tower 7010 SFF with a 1.0 TB Hard Drive.

When I check the Websites , the Hard Drive is listed as 3.5-inch.

However, when I measure it, it measures 4.0-inches.

I don't understand.

"3.5 inch " refers to the size of the platter(s) inside.
That is a standard measurement, with standard mount points.

 

[Ralston18]

Fun fact:

https://petapixel.com/2011/12/27/what-5mb-of-storage-looked-like-in-1956/

 

[Moonstick2]

And the reason it's 3.5 inch diameter is because the floppy discs were 3.5 inch diameter, same as you used to get 5.25 inch HDDs modelled after 5.25 inch floppies (and why the bays are called 3.5" and 5.25").