I have a program that will help, I have helped out many many many people.
My name should say trusted tech but they say im not on geekstogo enough.....
Download this program called pcwizard it really owns, people will start referring to use it after I post this. I bet.http://www.cpuid.com/pcwizard.php
after you install it there will be a menu to the left, click the icon that says mainboard when you roll your mouse over it.
It will list everything you need to know about your pc and what slots/busses you have.