Nginx php-fpm和Memcached的问题

I have an website wich is getting more traffic as usual in the past months. I want this website to server more users in the same amount of time without changing the Hardware. At the Moment i use Apache2 with Wordpress and Memcached. I wanted to know if i can use Nginx to get more performance on this site. When i have Nginx running on the Webserver with Wordpress and i run a test with 10000 users over a period of 60 seconds, i get only 600 succesfull answers the other 9400 connections get Errors. (mostly timeout). I have an website wich is getting more traffic