Occasionally a question will come up regarding the specs of a specific Mac product. My main reference for these questions is a great free application (donations accepted) called Mactracker. This gem has just about every bit of information you need or want to know about every piece of hardware and every operating system that has ever been sold by Apple. When it was released, when it was discontinued, amount and type of memory supported. You name it, the answer is there. I've kept a current copy of this for as long as I can remember, and there are even versions available for Windows and iOS.
This is one of my absolute "must have" apps, and I have it on both of my Macs, plus my iPad and touch. It's updated frequently and even allows you to add your own info. If you don't have it, download a copy today. Oh, and if you like it and use it, think about making a donation.