a typo sorry...my typing isn't the greatest today. And with that board there is no reason to suggest flashing the bios for that video card. and there should be no reason to flash the bios.
you shouldn't need to update any drivers on the board either but here's the link for the boards d/l's
http://www.asus.com.tw/support/downl...P4G8X%20Deluxe
here's the link for the latestbios should you wish to update it
http://www.asus.com.tw/support/downl...P4G8X%20Deluxe
I didn't find any agp drivers updates but the bios says it updates onboard SATA Boot ROM andd Improve AGP card margins but before flashing your bios you need to make sure you don't already have the latest one.
I'm not really sure what your saying the problems is if there even is one? other than asking what agp pci mode means is there some kinda problem with your video?