I need a mac mini to act as a data entry station and also a server for an image database. The image database lists 4 cores as min spec and support told me that was a serious recommendation. AFAIK (never owned a mac mini) this means a core i5 or i7. I heard that the recent ones are not memory upgradable so I'd like recommendation as to best year and processor to look for. If I understand correctly the i7 features hyper-threading which affords 8 virtual cores while the i5 affords only 4 physical cores, so I'm looking for an i7 which will be easy to upgrade in terms of memory and disk storage. What models/years should I be looking for? Are the servers essentially identical to the standard models? If not, what are differences except for software? Thanks for any insights.