Upgrading from Backup Exec 12 (not 2012) to 2014

Hi,

After some advice. We are currently running Backup Exec 12 (not 2012) on a Windows 2003 server. The plan is to install a new 2008 server and put Backup Exec 2014 on it. I read some where that upgrading from 12 is not possible but 12.5 is OK. Would i have to upgrade to 12.5 beforehand or would it not matter because i'm building a new server? Is there any documentation regarding this that you could point me to.

Thanks,