Thank you for your SPECS and the details of the symptoms.
I quickly reviewed the FOXCONN A7GM-S Board (
it's not Funncon ) at Newegg.com - Foxconn A7GM-S AM2+/AM2 AMD 780G HDMI Micro ATX AMD Motherboard - AMD Motherboards It is a good board and should support Win 7 X64.
I am guessing that you are installing this Win Bit 64 Build 7100 RC
with another system
like Windows Vista
or Windows XP
already installed on a different partition and running well
without any major issues. If that is the case I would further assume you might have several USB peripherals on the system configured to work in the existing OS. If that assumption is correct, I suspect one or more of the USB devices
attached to the MoBo or external USB ports might be interfering with the setup
My suggestion based entirely on all those assumptions is to disconnect all of the USB devices
including any USB Printers, Scanners, WeCam, Hubs, External HDDs and any Memory Card Readers installed in the case with USB connectors on to the MoBo, etc and then try Reinstall Win 7 again.
I will be interested to follow your progress.
Thank you and Good luck .