Hi:
First, you need to download and install the AMD chipset driver and reboot. You want the first file listed.
http://support.amd.com/en-us/download/chipset?os=Windows 7 - 64
You should be able to use all of the W7 x64 drivers (except the graphics driver) from the g7z-2100.
DO NOT USE ANY BIOS OR FIRMWARE DOWNLOADS FROM THIS LINK