View the motherboard photo at the Top, and also the Motherboard layout illustration, at a little over halfway down the page.
1) In the motherboard photo, all the way to the right side. View the Yellowish/Whitish connector, that has two columns of 12 socket holes.
This is where the 24-pin ATX main power cable plugs in.
In the motherboard layout illustration it is labeled - ATX1.
Here is a general example of this power cable, and respective connector on the motherboard,http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain24
Note that new Power Supply's, generally come with a 20+4-pin ATX main power cable.
This is so it can be used on the older computers that used a 20-pin ATX main power cable, and newer ones that need a 24-pin ATX main power cable.
Do not mix it's extra 4-pin power cable, with the 4-pin ATX +12 Volt power cable.http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain20plus4
Note the Lock on the side/middle. It has a hook on the end. The hooked end goes over a Tab, on the motherboard's connector.
The Lock works on the same principle as a see-saw on a playground.
You squeeze the top near where the wires come in, and this brings the hooked end away from the Tab, on the motherboard connector.
With the top of the Lock still squeezed in, the power cable is then removed USING the connector. (NOT the wires)
When assured that the power cable is plugged in tightly, and correctly, the hooked end of the Lock will be over the Tab, on the motherboard connector.
2) Look to the left of the Processor socket, and halfway in-between it, and the outside edge of the motherboard.
Whitish 4-socket hole square connector.
This is where the 4-pin ATX +12 Volt power cable plugs in. Power for the Processor. Note that it also has a Lock, with a Tab on the motherboard connector.
In the motherboard layout illustration it is labeled - PWR1
General example of power cable,http://www.playtool.com/pages/psuconnectors/connectors.html#atx12v4
That's it for the motherboard as for power cables that plug into it.
The rest of the power cables from the Power Supply, plug into the optical drive/s, harddrive, and card reader if used.
4) If your harddrive is an IDE (PATA) unit, it will use a 4-pin standard Peripheral power cable. Same with an optical drive that is an IDE (PATA) unit,http://www.playtool.com/pages/psuconnectors/connectors.html#peripheral
The computer case fan plugs into SYS_FAN1 connector, which is below the PWR1 connector. You may also have a computer case fan that uses the above power cable.
5) If your Harddrive, or optical drive/s are SATA, they will use a SATA power cable,http://www.playtool.com/pages/psuconnectors/connectors.html#sata
6) A Card Reader uses a power cable, that is also used for a Floppy Drive.
It is a 4-pin Small Peripheral power cable.
Has the same voltage wires; (Yellow - 12 Volts, Red - 5 Volts), and two Black ground wires, but a smaller connector, than a 4-pin Standard Peripheral power cable,http://www.playtool.com/pages/psuconnectors/connectors.html#floppy
The front of your computer is the Front Panel.
The area of wires on the motherboard, that the main wires from the Front panel go to, is the Front Panel header.
Although the Front Panel header has NOTHING to do with the Power Supply, I will include it also,
Motherboard positioned in computer case; Processor to the Top, Ram Memory slots to the Right;
The Front Panel header is at the bottom/right of the motherboard.
Black rectangle with 9 contact pins.
In the Motherboard layout illustration, JFP1 is marked under this header.
There are 4 pins across the Top row, 5 pins across the Bottom row.
The pins on the Top row are numbered EVEN.
The pins on the Bottom row are numbered ODD.
Starting on the LEFT side going towards the Right, Top row;
Pins 2, 4, 6, and 8. There is NO Pin 10.
Starting on the LEFT side going towards the Right, Bottom row;
Pins 1, 3, 5, 7, and 9.
A) Pins 1 and 3 are for the HarDDrive activity LED. (Light Emitting Diode)
Pin 1 is for the Positive ( + ) wire.
If the HDD LED is dim when the harddrive is active, switch the wires around.
B) Pins 5 and 7 are for a Reset switch, IF a Reset switch is used.
C) Pin 9 is N/C. Not Connected. Reserved for factory use.
D) Pins 2 and 4 are for the Power On LED.
Pin 2 is for the Positive ( + ) wire.
If the PWR ON LED is dim when the computer is on, switch the wires around.
E) Pins 6 and 8 are for the Power On switch.
F) Again, there is No Pin 10.
For additional questions post in a Comment.