CPU is measured in GHz, so look for this number as an indicator of processing power. Turbo Boost is also a winning feature when it comes to SOLIDWORKS.
CPU is generally split over a number of cores. Don’t get caught up on this though, SOLIDWORKS parts and assemblies can only make use of 1-2 cores at a time, due to the sequential rebuild nature for models.
Some assembly rebuilds, drawings with multiple views and simulations can take advantage of more cores at a time. CPU's such as Intel Xeons with more slower cores can cause a performance regression.