I was trying to look for the information you asked.
Actually, i will explain how i obtained these information.
Assuming that you are using an Intel Motherboard.
First step: Identify which motherboard it is
Second Step: Go onto the Technical Product Specification.
Third Step: Note down the ICH model like 82801GR
Fourth Step: Go onto the website http://ark.intel.com
Fifth Step: Paste the ICH category in the search box
Sixth Step: Download the Datasheet
Check in the Datasheet for the addresses that you are looking for.
Note: Example: http://www.intel.com/design/chipsets/datashts/307013.htm
Hope this helps a bit.