Hi jamshedkhan129,

I suggest you to install the Chipset, USB 3.0 Controller and Ethernet Controller drivers from the links provided below:

Chipset: http://dell.to/ZFF7ee

USB 3.0: http://dell.to/11rr8Fl

Ethernet Controller: http://dell.to/18oYP3G

Please let me know if you need further assistance.