Dell WLAN driver
ftp.dell.com/.../Network_Driver_CVYTR_WN_A01.EXE
Broadcomm Driver
ftp.dell.com/.../Network_Driver_PGHX7_WN32_17.0.2_A00.EXE
Bluetooth Driver
ftp.dell.com/.../Network_Application_X7R76_WN_6.5_A01.EXE
Mark the answer as resolved if the above steps work for you.