Ac Power Adapter What Happens If I Use A 30w Ac Power Adapter For My Extensa 5420 Instead Of A 65w Adapter?

What happens if I use a 30w ac power adapter for my extensa 5420 instead of a 65w adapter? - ac power adapter

I have an Acer Aspire 5420 for some reason the adapter that came with your laptop no longer works. Now I am with my cousin for your adapter Acer Netbook ... But does after 20 minutes to load and begin with the noise when you connect or disconnect power. They have something to do with the watts?