I tried to download OS Windows 7 on your MB X9DA7, but system asking where do I want to install it. It seems the system doesn’t recognize my new HDD. Would you please let me know what cause an issue?
You need to load the driver for controller. Please click the link below and select “Download the latest Drivers and Utility” under Links & Resources window.
http://www.supermicro.com/products/motherboard/xeon/c600/x9da7.cfm