I have a SQL 2012 server on VMWare that has 1 vCPU (I wasn't the DBA involved in the build so no lectures please.) It will occasionally take too long to respond to a ping routine that involves querying the SQL server resulting in all web servers being dropped from the pool and booting all users. CPU doesn't spike when this happens and we're running the vendor's recommended specs on this box.
The only thing that may point at a CPU issue is that the only wait stat that pops in Paul Randal's wait stats script (http://www.sqlskills.com/blogs/paul/wait-statistics-or-please-tell-me-where-it-hurts/) is SOS_SCHEDULER_YIELD at 99.99% of all waits. However, only a small fraction of a percent of the waits are signal waits. From what I've read that doesn't indicate that we're CPU bound, even with this wait type.
I want to recommend that they add a CPU but I want to be up front as to whether it's a guess based on best practice or we're seeing data that indicate things will get better. Thanks.