Yes and no. If its an international 710 and not originally from T-Mobile it will lack T-Mobiles HSPA+ band so 4G is out the window. Otherwise it should be able to connect. I know the North American phones are pentaband, so if the international phone is the same then you will be able to connect...
You may be able to do it, just make sure the new CPU is the same socket and similar TDP. I have upgraded CPUs in Acers, Dells, and HP laptops. But it may be a pain in the @ss, I had to take apart the whole laptop.