DDoS Attack

We are facing a DDoS attack. The attack is being performed from IPs from different part of the world. Our server CPU goes to 100% the moment we enable the website and server goes down. Our host provider says that he has put all filter and firewalls possible, he says that he has decreased connections from 200.000 to 100.000. He says that the best solution now is to enable another machine to have more CPU power to cope with the demand. Im looking for a provider that has experience in DDos and that could recomend a course of action. I dont know if there are faster and more efective solution than adding a additional machine.