The
9420 is based on
Excavator architecture while the
E5-2651 v2 is based on
Ivy Bridge.
Using the multithread performance as a reference, the 9420 gets a score of
26.2 k points while the E5-2651 v2 gets
426.2 k points.
Summarizing, the
E5-2651 v2 is
16.3 times faster than the
9420. To get a proper comparison between both models, take a look to the data shown below.