Forgive the dopey question, but What good is it that a HD gives you the larger size of it Unformatted if you can’t use a HD until it is formatted??
Because there are different file systems you could use to format the driver, which could result in different useable drive sizes.
Goggle to locate manufacturer’s web site. It may well be that logical block addressing limits the available useable capacity.
Full specifications of the HD are necessary to furnish a definitive answer to your question.
Did you read the manual accompanying the HD?
One other thing - hard drive manufacturers usually report their drive sizes using 1 GB =1000 MB = 1000000 KB . Operating systems will report 1 GB = 1024 MB = 1048576 KB. That causes the OS to report a “smaller” size that the advertised size. That might also be what drive manufacturers are trying to blame on fromatting.
Ok, then if that’s the case then why do they also give you a formatted size… if different file systems give you different capacity sizes than there shouldn’t be a static number to reflect a formatted HD size…