Best real world server environment for CI

[eluser]Devyn[/eluser]
Hi,
I'm wondering if anyone can give me best combination of optimized server configuration for a VPS to run CI. What kind of services should install for optimized php performance.
For e.g, backend server (apache,lighttpd), front server (nginx), caching (memcache,xcache,..)
I also would like to know pros and cons of each combination.
I've searched round the forum first but couldn't find the answer.

Welcome your advices. Thanks

[Edited] What I want to know is how to get maximum transaction per second in LAMP with extra daemons.