To the best of my knowlage its not an option in server builds, it has been put back into server 2008R2 by the guys on workstation.com, and does work well and i have used it on my server 2k8r2, they are working on the option for server 2012 as well as many other bits, So its just a waiting game and its only been out a short while anyhow, But from my first impression of server 2012 in a hyper v it seems to be nice and fast