most core 2 duo and core 2 quad cpu support Windows 10. here is user validated cpu benchmark for this pc.
Hello, I am trying to upgrade my inspiron 518 to windows 10. I am replacing the hard drive, RAM and processor. I have found the RAM and hard drive but I am having trouble finding the processor that will fit my computer and will work with windows 10. This is a project that I am working on so money is not an option. So, please, what processor will fit in the computer and work with windows 10 for a fresh install? 
Dell Inspiron 518 complete upgrade