Long story short I’ve got 2 servers one being a power edge r610 with 6 cores and the second server is a power edge r710 with 4 cores

if I want to take the CPUs out of my power edge r610 will they be compatible and work in the power edge r710

specs currently 

R610 cpu: Intel(R) Xeon(R) CPU E5645 @ 2.40GHz

r710 cpu: Intel(R) Xeon(R) CPU E5620 @ 2.40GHz