The
G645 is based on
Sandy Bridge architecture while the
E5400 is based on
Core.
Using the multithread performance as a reference, the G645 gets a score of
35.4 k points while the E5400 gets
26.8 k points.
Summarizing, the
G645 is
1.3 times faster than the
E5400 . To get a proper comparison between both models, take a look to the data shown below.