That's a 3000 shoved into a 2000 "rack" case, with a riser card modification and a backplane modification. There used to be a company out of California that sold the modifications (metal plates and screws really), I think they also sold/manufactured ToasterOven's ...
It's definately an A3000 motherboard though, check out the FAST RAM on the motherboard and the location of the SUPER DMAC and GARY.
