Oh I know! Pick me, pick me! (Lol!)
You mean WCD-44-rm5?
Spindle test. Actually finding out if the spindle motor is spinning the Spindle, at the maximum spindle speed in RPM's, the spindle is rated to spin at, (At maximum spin up)
Also a few other quick tests.
Basic construction of your harddrive. IDE (PATA) or SATA;
Inside the harddrive's case are;
1) Platters: They resemble CD or DVD disks, and are usually made of metal, or glass.
The Platters are coated with a magnetic medium. (Ferrous substance. Think Iron )
There may be 3 to 6 Platters, or more, inside the harddrive case. They are coated on both sides with the magnetic medium.
2) Spindle, and Spindle Motor:
The Spindle is part of the Spindle Motor. It is the shaft of the motor.
Comes out of the Spindle Motor, and the Platters are attached to it.
The Spindle Motor is designed to spin the Spindle (Shaft) certain Revolutions Per Minute, when called upon.
The maximum RPM's it will spin is stated for the harddrive unit.
Older harddrives were rated at 5400RPM.
(Slower before the above time period)
Newer harddrives usually spin up to 7200RPM.
Gamer type harddrives may spin 10,000 or 15,000 RPM's.http://www.behardware.com/articles/727-1/western-digital-velociraptor.html
3) Read/Write Head:
The magnetic medium on the Platters, is arranged by a Read/Write Head.
There is a Read/Write Head above, and below, every Platter inside the Harddrive.
The name indicates what the Read/Write Head does. When the Read portion of the head is activated, it reads what is ON the Platter.
When the Write portion is activated, it writes TO the Platter.
(The magnetic medium is arranged, by the Write portion of the Read/Write Head. It is arranged in a series of 0's and 1's.
0 being OFF, 1 being ON.
This is changed into Machine Language the computer can use )
4) Actuator Arm:
The Read/Write Heads are attached to an Actuator Arm.
The arm swings the heads back, and forth, across the Platter's surface.
(When called upon it can swing the Read/Write Heads back, and forth, at HUNDREDS OF TIMES A SECOND. -> HUNDREDS )
5) The Actuator Arms are attached to an Actuator Motor.
The entire assembly above is encased in a.....case.
It is assembled in a Clean Room. A room that is 99.9 percent dust free. The outfits the assembly technicians have to wear resemble a NASA space suit. They have to walk through an air corridor, and be b-lown off by air jets, before they can enter the Clean Room.
The harddrive's case has a small filter on it. This helps keep the atmosphere inside the harddrive, as it is outside the harddrive, but with NO moisture, NO dust.
On the bottom of the Harddrive case is an electronic circuit board. Controls the hardware inside the harddrive case, and is connected to the motherboard.
The Spindle test is to see;
1) If there is any axial, or horizontal runout. That is to say if the Spindle wobbles, so to speak. If so the Spindle Motor bearings are bad.
[Platters have to stay Dead Level. The Read/Write Head is spaced off of the Platter, by about .00003 of an Inch.
May be closer my figures could be off,
In comparison an average human hair is .003 of an Inch thick.
Due to the speed the Platters spin at, and the closeness of the Read/Write head to the Platter, the Read/Write Heads actually float on a cushion of air, when the harddrive is active.
When you hear or read the term 'Head Crash', it means one, or more of the Read/Write Heads, has touched a Platter, (Or Platters), and wiped off some of the magnetic medium ]
2) Spin up speed. How long it takes the Spindle Motor to spin up to the required RPM's. Actually, how long it takes the Spindle Motor to spin up the Platters, to the desired RPM.
Doesn't reach the RPM goal? Spindle Motor bearings are probably bad. (Or a failure in the electronic circuit board, on the bottom of the Harddrive. Doubt it. Usually just fails altogether )
The test indicates your harddrive is going bad. I would (Pronto) copy off my personal information. (Disk/s, thumb drive/s, storage on the internet, etc)