Hard drive RPM

[jekillen]

Hello;
Is there a utility for measuring the effective RPM of a hard disk?
A software tackometer?
I have IDE drives, SATA drives, both 7200 and 10,000 RPM,
as well as SCSI disks that are supposed to be running at 15k
RPM. I noticed that on the hard drive labels, those on the disk
case itself do not specifically indicate what speed they are supposed
to operate at. The two 10k SATA drives only had labels on the
antistatic packaging indicating that they are 10k drives. I would
like to verify the speeds of these drives. I am hoping that this is
not a case of misrepresentations that I have found on network
attached hard disk storage devices and Firewire drives.
I have one that was expressly advertised on the package to be
120 Gb capacity, and in fact only 111Gb are available for storage.
That is a 9 Gb discrepancy. A Fire wire drive I have is also designated
as 120 Gb and actually only has 117 Gb usable capacity.
Like 9Gb is enough for several operating systems. 3Gb is even
enough for an operating system.

Can anyone shed some light on this? (Storage device labeling,
and specifically, RPM specs)

I would ask the manufacturers but would be suspicious of bias
responses. That is what I got from one of them already.

Thanks in advance for responses.
The hard drives in question are running on FreeBSD systems
on homebuilt hardware. All AMD64 processors, ECS, Gigabyte,
and ASUS motherboards, Hard drives are Western Digital IDE,
SATA, and Seagate SCSI drives.

Jeff K