Kathi, Check out this site. If you look toward the right hand side you will see a listing of various revisions of Macs. You should be able to find your model pretty quickly. My G4-400mhz Sawtooth AGP Gigabit was bought in July of 2000. It has a blue power light. However the previous model that didn't have an AGP slot and only a PCI graphics slot had a greenish light. http://www.apple-history.com/ Whatever you do, do not underestimate the power of your computer. It may be old, but it still has a lot of Mojo. Unless you require it for heavy duty CPU processing, then it should continue to be a very useful tool. I have mush faster PCs that I can use, but I still prefer this old G4. There are a wide variety of things that you can do to upgrade your machine inexpensively. Most, if not all of these upgrades you can do yourself. There are small video clips online that can show you how to do these things. Once you've done it, your self-esteem will be through the roof. BIll