Since i cannot find the board D945GCL, it is a bit difficult to give an exact answer.
However i can explain how to get the answer.
If your board is D945GCXXX,and have the ICH Intel® 82801GB I/O Controller, so you can check on the ICH datasheet.
Identify your board correctly,
Identify which ICH you have.
Check on the correct datasheet.
All the best,