Didn't know where to post this so I through it up in here. What is the best strategy for accessing hardware addresses on your computer, or is it indeed OS specific? For instance, if I wanted to access some registers on my video card, or get access to a GPIO port how could I go about doing it in a protected mode setting? Or is it impossible/reliant on the OS to supply system calls for this? If this is the case what API would I utilize to access hardware under XP/Vista?