hello everyone i m quite new to ubuntu lucid 10.04 but for me is fantastic ,ive got just a small problem my sony vaio fw56z laptop (with intel 5100 wireless card) just connect 2,4 ghz to my time capsule and get 72 mb/s maxium speed so i guess it s in n wireless mode but in 2,4 ghz band.
using windows 7 i can get full 300 mb/ speed cos it connects in n wireless mode and 5 ghz band, so i m quite sure it s all about drivers but i really don t know where to start so any help would be appreciate

ps time capsule gives signal in both 2,4 and 5 ghz mode simultaneously
thank u very much and sorry for my bad english!