I found a little utility awhile ago only to just recently have tried it out. Its call.. 'PCI Information'. And basically, all it does is extract, on a low level, the essence of you computer's sub-system. It is similar to WPCREDIT, however, DOS based and lacks the abilty to change registers. While the utility doesn't 'do' anything, it manages to dissuade settings in the BIOS. For instance, 'setting' AGP 4x in the BIOS vs AGP actually being used at the indicated speed. Its well worth a look.. If you feel so inclined, I'll provide a sample output taken from my system.
The program is amoung the page here.
Sample output, here
The program is amoung the page here.
Sample output, here