I ran version 11 on a single core Atom (win XP pro, 2 gig memory, 120Gb SSD) for a long time, with no noticeable issues (several instances). They were small system mind you...a couple of trunks and a handful of extensions. I still have a Version 12, using Win 7 Pro, running on one of the same machines. All 32 bit machines, so no going to Version 12.5, or 14.
A lot may depend on the "load" you expect it to handle.
It may be that under certain conditions, it was discovered that "problems" arise.
There is nothing to stop you from testing it, but if you want to be sure that you (or more importantly, a client) won't have any issues, it would probably be best to go with the system recommendations.