If you do not have the Abit KN9-SLI motherboard manual, I would like you to download it, (Free), and follow along with me,
Abit Support > KN9-SLI motherboard > User Manual download page,http://www.abit.com.tw/page/en/motherboard/motherboard_detail.php?pMODEL_NAME=KN9+SLI&fMTYPE=Socket%20AM2&pPRODINFO=Manual
On this page go down to the heading > Mirror site, and click on the country nearest yours.
A small window will come up > Opening kn9_series.zip
If the empty circle to the left of Save File does not have a Green dot in it, Left-click on the empty circle.
Now go below, and left-click on > OK
This is a Zip file. A Zip file is used to send a large file more easily over the internet.
(It is a compressed file)
Watch the heading in the small download window that appears. This tells you where the file will download to.
It can download to your desktop screen, or the My Documents folder, or a sub-folder within the My Documents folder called > Downloads.
Close all windows see if the file went to your desktop screen. The file name is > kn9_series.zip
Then left-click on Start, and then on My Documents.
Then double-click on Downloads.
When you see the file name double-click on it.
Go to the left-side of the screen, and left-click on > Extract All Files.
Now click on Next, Next, and Finish.
You will be looking at a small window with a red PDF icon in it, and the file name underneath.
Double-click on this PDF icon.
There are three ways to go to the page I need you to go to.
1) Look at the Bookmarks menu to the left.
Scroll it down until you see the heading > Connecting chassis components, and under this heading > FAN Power Connectors
Left-click right on FAN Power Connectors
2) You can use the blue down arrow at the top of the PDF file, and go to Page 18.
3) The page number box is to the Right of the blue down arrow.
Put your mouse cursor in the page number box.
Press the Enter key
Look at the small rectangle with > CPUFAN1
Observe where it shows the pins that are Ground, 12V, RPM, and Control
Ground is Negative. Usually a Black or Green wire
12V is 12 Volt. Usually a Red wire
[It's a DC motor that is used for the Fan. DC uses a Positive (12 Volts in this case) connection, and a Negative connection. (Ground ]
RPM is Revolutions Per Minute. Colors vary from manufacturer to manufacturer. (More on this in a second) This is the wire that the computer (BIOS) uses to read how fast the fan is turning. How fast in revolutions per minute.
This is the wire that the computer (BIOS actually) uses to speed the fan up, or slow it down.
Colors vary according to manufacturer.
Your CPU fan connector only has a 12 volt wire, Ground wire, and an RPM wire.
Therefore you eliminate guessing which one is the Control wire, because the CPU Fan doesn't have one.
You should have a Red wire (12 Volt), Black or Green wire, (Ground), and another wire of some color. This wire is the RPM wire.
In the illustration for the CPUFAN1 connector on the motherboard, you will see a small rectangle on the left of the connector. Then four dots that represent the pins of the connector.
The small rectangle to the left represents a Tab. Also referred to as a Key.
This tab only allows you to connect the connector in one direction.
IF, when the CPU Fan connector fits on the motherboard's CPU fan connector, AND the wires do NOT line up correctly with the pins they're supposed to go to, you can change it.
You use a needle to take the wires out, and then put them back into the correct socket holes of the CPU Fan's connector.
At the end of every wire going down into the CPU fan connector, is a female metal terminal.
Looks like this,http://www.alibaba.com/product-gs/336134982/molex_female_crimp_terminal_connector/showimage.html
Use the Zoom In icon at the top ( + ) to enlarge.
The left side of the Molex (Female Crimp) terminal connector is where the wire comes into.
The two tangs that stick up all the way to the Left, are crimped around the insulation of the wire.
Coming to the right a little bit, are areas of the connector that are crimped on the bare end of the wire.
Going all the way to the Right side, you will see tangs that stick out the sides. Two of them.
You can see the one in front clearly, but just the tip of the one on the other side.
Crude illustration > This = the side of the connector > l.
This equals the side of the connector with the tang sticking out > l/
Where the wire comes into the connector is the BACK of the connector.
The end of the connector that plugs in is the FRONT of the connector.
The needle goes up into the socket hole of the wire, from the Front.
It then depresses the tang down.
(Slides up the side of the female terminal, and the inside of the socket hole)
Now go to the other side, and depress that tang down.
Now you can slip the wire out of the Back of the connector.
(You may have to use a bright light, and possibly a magnifying glass to see the tangs. After you know where they are, set the magnifying glass down, and depress them)
When you get the wire out, gently use the needle underneath the tang, to ease it back up if it is flat against the female metal terminal.
Use care because if you bend the tang too far up, it will snap off.
All wires removed, put them back into the socket holes of the connector where you need them.
Have questions, or need clarification to what I have stated, post back in a Comment.
(On the CPUFAN1 connector on the motherboard the tab, or key is to the Left;
A) The top pin is for the Ground wire. (Black or Green wire)
B) The next pin down is for the 12 Volt wire (Red)
C) The next pin down is the RPM wire
(The last pin is for the Control wire which your CPU Fan doesn't have)
Sorry I was so long and 'Windy'.