3.6 Installing the Floppy Drive, Hard Drive, & CD-ROM
3.6.4 Connecting power cables to the floppy drive, hard drive, and CD-ROM
Power Voltage Requirements
Small cable drive connectors from the power supply provide power to the floppy, Hard Disk Drive (HDD), and the CD-ROM. The cable connectors have a female 4-pin plug that connects to a male 4-pin connector at the rear of each drive. The pin-outs or wire scheme are color-coded in order to identify the proper voltages of the wires.

Two different power voltages are required for the proper functioning of these drives. The circuit board and the logic chips that each drive uses are designed to use the +5v power. The drive motors use the +12v power. 

Connecting the Drives
Attaching the power cables to the drives is simple because all the connectors are keyed and therefore can only be inserted one way.

  • Floppy drive – Identify the proper connector that goes with the 3.5" drive. These connectors are usually the smallest plugs coming out of the power supply. Push the plugs in gently. Do not rock them back and forth to secure a connection.
  • HDD and CD-ROM – Identify the proper power connectors for these drives. They are larger than those for the floppy, and on these power plugs sometimes the labels will be P1, P2, P3, and so on. They are harder to push in so rock them gently back and forth if needed until they snap into place.

As always, double-check all of the work, making sure all power plugs are properly inserted and secure.

Lab Activity  (PDF, 12 KB)
  In this lab, students will install the floppy drive, hard drive, and CD-ROM drive. Students will also install the ribbon cables for each drive.
    
Video  (2:48 min)
  Installing the Floppy Drive, Hard Drive, and CD-ROM Drive