I suggest you go to the INTEL Support website. You should go to this page. https://downloadcenter.intel.com/default.aspx
On that page figure out what Motherboard you have. Use that number to locate the page for that board. Then click on that board.
First you should look for the word 'Documentation" Clicking on that should get you to the Manual for your board. Once you get
that page up look for any reference to the manual for that board.
Download the manual for that board. Most of those manuals are
in .PDF files so you will need to have a pdf reader installed on a
machine you can use. Open the manual in the pdf reader and look for instuctions explaining how and where the cables are laid out on the Board. This set of connections is usually called a "Front Panel".
NOTE: These plugs are often shown with + and - signs. You may have to try turning the plugs 180 degrees once of twice
in order to get them working right. The plugs are usually labeled
as follows. PS = Power Switch, HD LED= Hard drive LED lamp.
RESET = Momentary Contact Reset Switch. (Do not use unless
necessary). and Pwr LED = Lamp that lights up telling you the machine is powerd up and ready to go. I strongly suggest that
you do not "guess" at which pins are which. Look them up. That
manual will explain everything you will need to know. Look at the pictures. that will help you understand the layout. Best Wishes.