if you have old keyboard at least partially working, try to put it back. If it works. probably the problem is with the new keyboard.
If the old one also doesn't work, the problem is probably with motherboard connector or software (less probable). To check the software problem, i think it's possible to load the laptop from any linux live cd or some other OS different from what s installed on your pc.
Please be aware i'm not professional pc service man and these are just common thoughts (hope helpful)
