If you want to get technical there is no such thing as a DM3. It's a nickname given to Dye Matrix's when the DM4's & DM5's came out. What you have is a Gen-E Matrix, probably with a TMC ( The Matrix Center ) Board in it.
The Ironmen Matrix I have at my house right now has a TMC board in it. The TMC board is an exact copy of the Dye Matrix boards, except the boot up displays TMC instead.
Here's a picture of my old brick.