I have an Encore MDX (also a dual 1.8GHz) in my OS 9 MDD. It did not improve CodeWarrior performance much, possibly due to the missing L3 cache and CodeWarrior is pretty diskbound anyway. However, it was noticibly faster in Virtual PC.

Click to expand...

I know that the Duet only has single CPU support under MOS9, maybe the same for the Encore?

These days I'm running 10.5.8 mostly, and when I have to drop back "to the good ol' days", Classic under 10.4.11 is fine. I can boot into 9.2.2, but as it doesn't recognise the SATA card, it is a two stage boot for the return trip, first stop-over at Tiger on IDE0, then a connecting flight to Leopard on SATA1 (SSD) or SATA0 Plattersville.