Are we talking video card? Because I recently bought a GTX 580. I don't want to have to buy another expensive card.
It depends, I know somebody from finland that had about the same, his SSD and mobo got fried.
You might not need to buy a new 580 but as it seems your mobo is fried at some points, that explains why your internet isnt working and it doesnt recognize the keyboard in the bios...
I think you'll probably need to buy a new motherboard and you'll be fine. But first test i'd test all of the hardware in another pc (and visa versa) to see if everything else still works fine.