The Four Pin Panel Mount Connector
The four pin panel mount connector is a common power connector in PCs. It’s used for everything from floppy drives to hard disks to extra video card or motherboard power.
Panel mount means it has features built into it that allow it to be fixed into an enclosure’s hole or cut-out. This can reduce stress on the electrical solder connections within the connector.
Peripheral Power Cable
The four pin peripheral power cable shows up in many PCs these days because it powers the floppy and optical drives. But it’s also used for all kinds of things like add-on fans, extra motherboard power and supplemental video card power. It’s a Molex series 8981 connector which is designed to carry high current. The connector is shaped so it only fits in one way so you don’t have to worry about inserting it incorrectly.
Newer computers tend to put most of their load on 3.3 and 5 volts but older ones often still use the four pin peripheral power connector. It’s the same kind of connector as used on a USB cable but it provides the two 12 volt lines that are commonly associated with ATX power supplies.
It only fits into the motherboard connector on one end so you can’t plug it in wrong but you can sometimes force it in if you really try. You shouldn’t do that because the motherboard connector expects a lot of current and you could damage your computer. It’s not that hard to tell the difference between this and an 8 pin EPS cable though since both use the same Molex Mini-fit Jr. connector. They are polarized differently too so you can’t plug them in the wrong way unless you try very hard.
Motherboard Connector
This is the main power connector for the motherboard. It’s 4 pin panel mount connector also known as an ATX power connector, and it provides 12 volts of power to the motherboard. The motherboard also has several fans that connect to this connector, and it’s often referred to as the “SYSFAN” or “CPUFAN” connector in motherboard manuals.
The motherboard has several USB connectors that connect to the front of the case or other USB devices in the computer. The motherboard also has a connection for the microphone input and output jacks on the front of the computer. Most modern motherboards also have a connector for RGB type lighting. This allows you to synchronize the lighting in your chassis with the motherboard’s lighting, giving it a very unique look.
There are also various expansion card slots that connect to this connector, including PCIe connections for the graphics card. The motherboard also has a connection for connecting a thermistor cable that can monitor the temperature of critical components and connected devices.
This is an older, serial port that was used in IBM PC-compatible computers during the 1980s and 1990s. It has keys that indicate its correct orientation, preventing it from being plugged in incorrectly. It has since been replaced by USB, which offers higher transfer rates and more versatility. This connector is usually found on a separate expansion card, but it can sometimes be integrated into the motherboard itself.
8 Pin 12 Volt Cable
This is an aux power cable which plugs into the motherboard connector. It’s often confused with an EPS 12 volt power cable which looks similar but has two yellow wires instead of one black and one red wire. Trying to plug an EPS connector into the motherboard will cause a short circuit and potentially damage the components inside the computer.
Older computers put most of their load on 3.3 and 5 volts but as time passed they started to need more 12 volts. This cable was added so more could be shifted to the motherboard from the power supply’s 12 volt rail. It also adds two extra 12 volt pins which may be used for other things on the motherboard.
If you need more than the maximum wattage listed for this connector and wire, a splitter or tee can be used to connect more than one wire to it. Just make sure the power cables have the same polarity. It’s not good to mix up positive and negative polarity as this will negatively affect the voltage output on either side of the connector. Also, don’t try to use a 20 pin + 4 pin connector (or 24 pin) for the motherboard connector as this will not fit and is dangerous as it will result in a short circuit.
4+4 Cable
Several power supplies come with what is called a 4+4 cable which consists of two separate 4 pin pieces. If you plug both of them together they make a regular 8 pin 12 volt power cable. But each half can also fit into a motherboard’s 4 pin connector just fine since the motherboard connectors have both square and rounded off corners which prevent them from being plugged in the wrong way.
But even if you have one of these 4+4 cables it is important to know that it doesn’t connect to the CPU power connector on your motherboard – instead you need to use a solid 8 pin or a 6+2 pin connector. If you try to plug the 4+4 cable into a motherboard’s CPU connector then you 12 volt 2 pin waterproof connector will not be able to run your computer because the 8 pin EPS power connector on the motherboard expects high currents which will kill it.
The way you connect your wires to the 4 pin panel mount connector is through solder-cup connections. The panel mount connector has two solder cups which you can place your stripped and tinned wires into. After you place them into the solder cups you simply solder them and then heat-shrink them. Then you can reassemble the connector and it is ready to go. Each solder point is clearly marked and keyed so you can’t accidentally attach it to the wrong wire.
