netinstall vs FTP

I tried to put v3beta7 on a 112 that was running 2.9.42 and I am seeing the same 100% cpu usage everyone talks about when using the FTP method of upgrade. I will do all the things suggested in the posts but my question is what is the difference between netintsall and FTP for the beta software???
thanks
Kenny

I assume there is no difference for these installation methods, when you are upgrading from 2.9.42 to 3.0beta versions.