What's the noise?

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no, not at all. The HD never touches. If it were to ever touch the HD would be dead. Nothing like a record
 
Lots of things in a drive make noise.

You've got the application and dissipation of data being done by several air-gliding magnetic armatures clicking as their sollinoids change direction.

The platters themselves don't make any noise really with the way they're mounted, but the motor that keeps them at speed throws a fit on startup and priming.

Then there's the vibration, though that's usually only heard if the drive isn't mounted good.

I'm sure there's a howthisworks thingy around somewhere for HDD's.
 
yeah, the arm never touches the platters. it picks up minute phase changes on the platters (magnetic charges). you may hear a little of the vibration from the platter spin, but alot of the noise is from that arm searching the HDD for complete files, considering that the data is no usually in sequential order on the HDD more often than not, it has alot of movement involved. Heres a nice little bit I found (saves me from having to type all this crap):



Let's say you do something simple like double-click on the icon for a spreadsheet file. This simple act, on many computers, can take 20 or 30 seconds to complete, and all during that time the hard disk is churning away. The hard-disk access light flickers and the drive might make a whirring, whizzing or high-pitched whining noise. If the mechanism in the drive is loud, you definitely know that something is going on!

In the article How Hard Disks Work, you can see that there is an arm that holds the read-write heads. This arm can move the heads to tracks near the hub or near the edge of the disk. A normal hard disk is 5 inches (12.5 cm) or so in diameter. This arm, therefore, can move about 2 inches (5 cm) across the face of the disk.

The speed at which this arm can move is astonishing. The arm is very light, and its actuator is powerful and precise. The arm can slide across the face of the disk hundreds of times per second if it needs to.

If you think about how a speaker works, there is not much of a difference. A speaker is moving a lightweight cone back and forth hundreds of times per second to generate sound. As the hard-disk arm moves back and forth rapidly, it sets up vibrations that our ears hear as sounds.

Why, when you click on a simple spreadsheet file, would the disk's heads have to move so much (20 or 30 seconds worth of movement sometimes)? There are three things that cause all the movement:

* To start a spreadsheet application like Excel, the hard disk has to load the application itself along with a number of DLLs (dynamic link libraries) that support the application. The total size of all these different files might be 10 to 20 megabytes, and the files are scattered all over the disk. Loading 20 megabytes of data takes a lot of time and requires the disk head to move thousands of times to retrieve all the pieces.

* The data file itself has to load. The operating system (OS) has to move the head to the drive's directory to find the folder, make sure the file name exists, and then discover the location of the file. Then the OS may need to read dozens of tracks scattered all over the drive to access the file.

* If the physical RAM is full, then during the loading process the OS will have to unload parts of physical RAM and save them to the paging file on the disk. So while the OS is trying to load the spreadsheet application and all the DLLs and the data file, it is at the same time trying to write millions of bytes of data to the paging file to make room for the new application. The drive head is moving all over the disk to accomplish these intermingled tasks. See this Question of the Day for details.

Altogether, clicking on a single icon may cause 40 or 50 megabytes of data to move between the drive and RAM, with the disk heads repositioning themselves thousands of times in the process. That is why you hear the drive "churning" -- it's doing a lot of work!
 
killains45 pwned this thread lmao.

i just know there are heads in the HDD and they move lightning fast, when they read and write they make little tiny vibrations. when thousands upon thousands of those vibrations happen in a matter of less than a second they produce a small hum. you work your HDD for a few seconds or longer and those hums add up together to make a louder hum or rattle. newer HDD's like mentioned are lubed up better and the arms are smoother and the plates can move faster while producing less vibrations.

adding spacers or using a HDD enclosure should almost mute the drive in an average size case. MY HDD is pretty much silent even when benching it, but it's only 7200RPM SATA drive...so not really "fast" to some people.
 
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