wireless card 1395 not working even drivers are installed

Hi

Plz help

with wireless 1395 on inspiron 1720 having windows vista 32 bit

problem is wireless does not work when i start my computer after long duration, at time it does not even show the card in device manager

i have updated the drivers and even redone windows.

Secondly when i try to reinstall drivers of wifi after removing them from control panel, it shows an error that operating system not supported

PLZ HELP URGENTTT