Not a problem, but it would be handier to have the manufacturer Name, and Model Number.
(Back of computer on a sticker, next to the Windows product key, or up on the side of the computer tower )
SMPS = Switched-Mode Power Supply. The style used in personal computers now,http://en.wikipedia.org/wiki/Switched-mode_power_supply
A) Main power cable:
There are three styles;
1) The old AT style that has two separate connectors. The connectors BOTH connectors have BLACK wires towards one side.
The connectors also have ONLY one way, (Direction), they can be plugged onto the motherboard.
This is due to the Lock, and Locating Tab on the motherboard connector/s, and the main power cables connector/s.
When you can plug the connectors on the motherboard, with both connector's BLACK wires facing each other, (They will be in the middle), you have them installed correctly,http://www.playtool.com/pages/psuconnectors/connectors.html#oldpc
2) The newer ATX style. Uses one power cable, and connector.
First style to come out was the 20-pin ATX main power cable,http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain20
20-pin ATX main power cable's connector, has a LOCK on one side.
This Lock locks over a Locating Tab, on the female motherboard connector.
To remove this power cable you squeeze in on the Top of the Lock.
The Lock operates like a see-saw on a playground. When you squeeze the top in, you remove it's hooked end away, from the Locating Tab of the motherboard connector.
To be ensured that this cable is plugged in tightly, and correctly, the Lock's hooked end will be over the Locating Tab, on the motherboard connector.
3) The newest style is the 24-pin ATX main power cable.
As computer hardware evolved, and became better, it demanded more power.
The extra 4 pins of the 24-pin ATX main power cable provided this,http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain24
[ Aftermarket power supply manufacturers, provide power supply's with a 20 + 4-pin ATX main power cable, usually.
You can use it as a 20-pin ATX main power cable, or use the additional 4 pin cable, and use it as a 24-pin ATX main power cable ]
4) Motherboard didn't provide enough power for newer Processors.
The 4-pin ATX +12 Volt power cable was brought out.
(Has Lock with Locating Tab on the motherboard connector, also)http://www.playtool.com/pages/psuconnectors/connectors.html#atx12v4
5) Motherboard didn't provide enough power for high-end graphics card.
4-pin ATX +12 Volt power cable didn't help.
The 6-pin PCI Express power cable was brought out,http://www.playtool.com/pages/psuconnectors/connectors.html#pciexpress
Plugs into a graphics card.
In all power cables, Red wires are 5 Volts. Yellow wires are 12 Volts. ALL Black wires are Ground wires ]
Next in line was two versions of the 8-pin power cable.
A) 8-pin EPS +12 Volt power cable.
Originally brought out for server computers, that has multiple Processors.
Plugs into the motherboard.
B) 8-pin PCI Express power cable.
Brought out for more power, than a 6-pin PCI Express power cable could put out.
Plugs into a graphics card.
(6-pin PCI Express power cable is capable of handling 75 Watts.
8-pin PCI Express power cable will handle 150 Watts )
If you have an IDE (PATA) harddrive, a 4-pin standard Peripheral power cable is what you need. ('Molex' is the slang term for it's connector)
If you have a SATA harddrive you need a 15-pin SATA power cable.
IF, your SATA harddrive has a provision for a 4-pin standard Peripheral power cable, AND a SATA power cable;
ONLY USE the SATA power cable!
If you use both you will burn out the harddrive. Maybe not immediately, but I assure you down the road you will.
(Do not use just a single 4-pin standard peripheral power cable, either)
Optical drive/s use a 4-pin standard Peripheral power cable, if they are IDE (PATA) units.
If they are SATA units they use a SATA power cable.
The old Floppy Drives use a 4-pin small Peripheral power cable.
Same cable plugs into a Card Reader, also.
The plastic front of your computer is the Front Panel.
The area of contact pins on the motherboard, that the cables, (Wires), from the Front Panel go to, is the Front Panel header.
Sometimes abbreviated on the motherboard as;
F_PANEL 1, or FP1, etc.
I will need to know the computer manufacturer name, and Model Number, (HP = Product Number, or P/N), or the manufacturer name, and Model Number of the motherboard, to TRY to provide this information.
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