A real answer would be nice!
Google is, as you know, absolutely no substitute for a real forum search engine.
First you said that phpbb sucks for big forums (search table problem), now you say that it´s the current server hardware that can´t handle the forum search? Well, if that´s really the case then let us know what it would cost to buy or rent a new server or to upgrade the old one, then we can can start donating money...