Doesn't matter if the mobo is only a year old. I have seen them bad only after a month. The one thing you can try is buying a usb wireless adapter and then seeing if you can connect. If so then your NIC is no good. Did you try running a ping/trace route?
How to run a ping, if your computer is Windows Vista or Windows7:
Click on the "Start Orb" and then type "Command Prompt" in the "Start Search" field.
From the search results, click on the "Command Prompt" icon that's listed under "Programs."
After the "Command Prompt" window is open, type: ping -n 500 [hostname] > ping.txt
(without the brackets)
Example: Example: ping -n 500 YourHostedDomainName.com > ping.txt
Depending on the network speed, this command will run for several minutes. Once the diagnostic is complete, the results will be saved in a filed named ping.txt.
How to run a traceroute, if your computer is Windows Vista or Windows 7:
Click on the "Start Orb" and then type "Command Prompt" in the "Start Search" field.
From the search results, click on the "Command Prompt" icon that's listed under "Programs."
After the "Command Prompt" window is open, type: tracert [hostname]
(without the brackets)
Example: tracert YourHostedDomainName.com