Internal Connector Guides

This connector has two rows of five pins and is normally used to connect an external port to header pins on a motherboard. This connector is typically used for USB, or Serial (DB9) ports.

This connector is typically used to add a DB25 Parallel Port interface. Most of today's motherboards do not have this type of connection.

34-pin sockets are used for floppy drive cables. The floppy controller on a motherboard is a 34-pin header, as are the connections on 3.5 inch floppy drives. "Antique" 5.25 inch floppy drives used a card-edge connection to interface to the floppy cable, so many floppy cables will come with both socket and card-edge connectors. For many of today's computers, floppy drives are no longer standard equipment.

This interface is still in wide use. It is found on IDE/ATA hard drives, optical drives, and tape drives. Many motherboards come with a pair of 40-pin controllers (described as primary and secondary). Each controller can handle one or two drives, so most standard PCs can have a maximum of four IDE drives. A few years ago, the IDE/ATA standard for hard drives was improved, and a new cable was specified. This new standard is referenced by many names—Ultra ATA, Ultra-DMA, Ultra-66/100/133, etc. Ultra ATA hard drive cables use an 80-conductor ribbon cable, although the same 40-pin socket/header interface is still used.

50-pin socket connectors are used for basic internal SCSI buses. The connector looks identical to a 40-pin IDE interface, only with more pins. The 50-pin interface is used for older, narrow SCSI buses.

The 68-pin socket internal connection is the same size and shape as the external MD68 pin interface used for SCSI devices and cables. However, the internal flat ribbon version does not use any thumbscrews or latch clips to hold the connector in place; it is held in solely by the friction of the connector and pins. The 68-pin flat ribbon connector is unique in that the connectors on the cable are male, and the interfaces on SCSI drives and host controllers are female. This connector is very commonly used for wide SCSI buses.

The common 5.25 inch 4-pin power connector is impossible to miss inside a PC case. A computer's power supply normally provides several of these connectors, which mate to male interfaces on hard drives, CD/DVD drives, and other internal devices. Because these drives often have a 5.25-inch form factor, the power connector itself became known as a "5.25" connector. The plug is also commonly referenced as a "Molex" connection, after the well-known connector manufacturer. The connector is typically white in color, and made from hard nylon or similar plastic material.

The Serial ATA (SATA) Power connector has 15 pins and is slightly larger than the SATA data connector. One main advantage the SATA power connector provides over the 4-pin power connector is a pin that provides 3.3 V of power. Certain SATA drives have specific power requirements.

The Serial ATA (SATA) Power connector has 15 pins and is slightly larger than the SATA data connector. One main advantage the SATA power connector provides over the 4-pin power connector is a pin that provides 3.3 V of power. Certain SATA drives have specific power requirements.

The 32-pin SAS connector is typically found on SAS controller cards. SAS technology is a replacement for SCSI and is typically used to connect hard disk drives in data center applications. However, this connector can be used to connect a SAS expander. This connector is also referred to as the SFF-8484 connector. In many cases the 32-pin connector is being replaced by the mini-SAS connectors due to mini-SAS' smaller form factor.

SFF connectors grew from the effort to make fiber connections smaller. In a rack or closet environment, space for several connections is limited, and thus manufacturers sought a way to increase port density. A standard was developed for smaller connectors called SFF (Small Form Factor). There are many different types of SFF connectors, but they are all smaller than normal ST or SC connections.