You don't list the type of wireless adapter, but from the error message it sounds like it uses an Ethernet connection to the PC.
It also reads like you haven't installed the nVidia driver
package for your mainboard, which has a 790i Ultra SLI chipset. It includes the drivers
for the network adapter. I suggest getting the latest version fromm www.nvidia.com
The Windows 7 installer includes a lot of drivers, but it may not cover nVidia chipsets. I vaguely recall having to install chipset drivers for my Compaq notebook (AMD CPU, nVidia chipset).