Beats audio driver

hi,
i lost my genuine win 7, by installing new windows 8, i got a problem of drivers espeially beats audio driver.
Can anyone help me how to install hewklett-packard drivers(especially beats audio driver) for my notebook with windows 8 ..?
Hp envy 4-1019cu Notebook. PC

secondly, google just shows the result of hp envy 4- 1019tu ultrabook, What is the difference b/w tu and cu here... ??