ibuypower uses Asus, Gigabyte, and MSI motherboards for AMD systems. No telling which motherboard is in the TigerDirect system. In fact there are no brand names for most of the components. You can contact TigerDirect and ask about the model they are selling.
You can also contact ibuypower direct:http://www.ibuypower.com/
You'll need two 120mm fans - one for the bottom front and one for the top rear.