What Is a Hard Drive

A Hard drive is the computer component that holds all of the data in a computer. It holds all of the boot information in the computer so that the computer can properly run. There are different types of devices that store data. The most common is the hard drive(HDD) and the next fastest is the solid state drive(SSD) and the current fastest is M.2 which is connected directly to the bard. All of these are non-volatile which means that if the power is off, the drive will still be able to retain all of that data. A HDD uses a disk to store all of the data. A SSD uses semiconductor chips to hold the data. This means there are no moving parts which makes the SSD faster than a standard HDD. Then there is M.2 which is like a SSD with no moving parts while M.2 connects directly to the board making it the fastest of them all. HDDs and SSDs connect to the computer using a SATA cable.

You can click on the images to see a closeup.

The parts of a HDD are the platters, spindle, read/write head, actuator arm, actuator axis, and the actuator.

Platters - They are the disks that hold all of the data for the computer. There are sometimes multiple platters in one hard drive. The data on a platter is held by having a certain charge on a specific point on the platter. This data is read as 0’s and 1’s by the computer bases on if that point has a positive or negative charge.

Spindle - It is the axis driven by an electric motor to spin the platters in order to put the data in the right spot on the platter.

Read/Write Head - it is the head of the actuator arm that sits a fraction of a millimeter over the platter. This head will write data on the platter by changing the charge of that point on the platter. It reads data by receiving the charge on the point and sending it to the computer which then deciphers it as 0’s and 1’s.

Actuator Arm - It is the arm that has the read write head on it and it moves the read write head back and forth so that it can write and read data at the right points on the platter.

Actuator Axis - It is the axis that moves the actuator arm so that the read write head can read and write data on the platters.

Actuator - It is the component that moves the actuator axis the right amount to read and write the data on the right spot on the platter

The parts of a SSD are cache, NAND flash memory and the controller.

Cache - It holds all of the data right there ready to be used.

NAND Flash Memory - It is the part of the SSD that allows it to hold data while power is not being supplied to the computer.

Controller - It controls where all of the data will be stored and when to send and receive certain pieces of data.

A HDD is a computer component that does not need much service to keep it running. Opening the case of a hard drive is not good because dust can get in the area where the platters spin and cause the read write head to collide with the platter. when this happens it can wipe and corrupt data that is in that location on the hard drive. Because hard drives have a read write arm so close to the platter, just one dust particle could cause the HDD to go bad. Another way to take care of the hard drive is to put it in the proper slot in the computer case and leave it there. Too much movement could cause the read write head to collide with the platter and render the HDD useless. Signs of problems are: scratching/clicking noises, slower speed, and when the computer does not sense the HDD at all. Another good thing to keep your HDD fast is to clean the disk which is using software to put all of the program files close to each other. closer files mean that the HDD can access these files faster making your computer faster.

Troubleshooting a hard drive is not that hard because there are not many things that can go wrong with the HDD.

1. You should always have a known good HDD so that you can determine where the problem is. It is smart to label the known good vs the original as seen in the first image.

2. Signs of a bad hard drive include, unusual noises from the HDD and data loss which includes disappearing files and slower speeds. If there are any of these symptoms, you should try a known good HDD. If that works you should just get a new hard drive. another thing to sense if a computer sees a HDD it to open the boot selection on startup. image 3 represents when the computer sees the HDD while image 4 represents when the computer doesn't recognize the HDD.

3. If your computer is not detecting the HDD, as seen in image 2, you should make sure the HDD is plugged in right. In the 5th image you can see that the black SATA cable is plugged into the SATA port in the mother board. Once you have checked that the SATA cable is plugged into the board, you should check if the power cable and the SATA cable connect to the HDD. This is shown in image 6. I am holding the power cable and the SATA cable connects right next to that. If this does not allow the computer to connect to the HDD go on to number 4.

4. Now this means that the HDD could be bad, the cable could be bad, or the port could be bad. Try moving SATA ports on the motherboard and rebooting the computer. There are 3 ports on the motherboard shown in image 5. If that doesn't work and the computer still doesn't find the HDD, go on to number 5.

5. From here you are going to take the known good HDD and plug that in to your computer. If it still doesn't work it is a problem in the SATA cable and you can replace it with a known good cable. Your computer should work now with the original HDD. If however, it works when you use the known good HDD, you know that the original hard drive is bad and you should replace it with a new hard drive.

6. When solved, your OS should load and you should see something like the last image.