No Wi-fi hardware in 12.04.2 but connected in 13.04

[Shashank SVRSN]

My friend bought  a new Dell Inspiron 15 (Model No: 3521) with "Atheros 
AR9565 Wireless Network Adapter".

First I installed Ubuntu 12.04.2 LTS on it where Bluetooth seemed to be 
enabled but no sign of any wi-fi hardware availability in the 'Network 
Connections' tab. Tried backports, Madwifi but in vain

Now I erased and installed Ubuntu 13.04 and everything is working like a 
charm

Now I'd like to know if -- my 12.04.2 image/writing method was corrupt?
                                     -- OR this particular hardware was 
unsupported by 12.04.2?

Regards
Shashank