Here is the model: http://lowendmac.com/2006/mac-mini-early-2006/
I bought it used with 2 GB of RAM, and I upgraded the processor to a 2 GHz Core 2 Duo.
The Mac mini has 2 RAM slots, the first one had a 2 GB RAM stick in it, so I tried putting a 512 MB stick in the other slot. When I pressed the power button, it didn't turn on. Removing the added stick solved the problem.
