Hi Mrle and welcome to Windows 7 Forums
Your board uses the Realtek RTL8111E LAN chip. Download the
driver from here (the 2nd one down,
Windows 7 and WinServer 2008 R2 Driver):
Realtek
This is a zipped file, so select the option to save it to your computer when downloading. Now extract the contents of the zipped file and then, with reference to
Device Manager - Install Driver - Vista Forums, proceed to install the
driver. Obviously, you will need to expand the
Network adapters sub-category and then, as you have a 32-bit OS, point to the required location. If you have downloaded the files to your download directory and extracted them to the default, this will be:
C:\Users\<UserName>\Downloads\Driver_Win7_7050_01162012\Driver_Win7_7050_01162012\Windows 7\32