While there are differences between visors, the basic concepts are the same = no ballooning (other than stuff you just don't care about), don't assign too many cores, make sure the storage is fast enough.

Also - we currently have no info on what's wrong

read this, and the links, get an idea where Paul's coming from then run te query to see what your main waits are and post

http://www.sqlskills.com/blogs/paul/wait-statistics-or-please-tell-me-where-it-hurts/

also - try running sp_blitz, this may also help - run it, check the links, post te results of anything you don't, or are not sure you, understand

http://www.brentozar.com/blitz/

This won't solve anything, but it's a start.