Optiplex 390 CPU upgrades

May not be worth the effort but here goes. I have an Optiplex 390 with an I5 2400 3.1ghz and it works great but I am getting a Optiplex 3020 that has an i5 4590 3.3ghz cpu. Biggest reason for getting the 3020 it was cheap and it has a better processor the problem I am having some of the programs on the 390 I need to manually install and it could be a PIA to get it set up correctly. One of the ideas I had ( Geek Squad @ Best Buy ) thought it may work simply swap out HDD's. Not sure if it will work since one has a Sandybridge other Haswell. Next idea can I take the 4590 cpu out of 3020 and put it in 390?? If that would work what is involved??

Thanks