After spending a lot of time by taking day offs from work, I finally figured that there were two settings on my BIOS screen which disables MAC to power up the ethernet.
1.) Hyperthreading
2.) Intel VT

Disabling both actually worked and now I'm able to go online, however, this wasn't the case before, ethernet powered up even with hyperthreading ON and VT ON on my first install. So will do a research on that as well, but need to show my face at work. Bye