They say you can not install 2 different CPU on a Z600 (it is a V2)
C'mon then, you people have a look at the pictures I'm going to meet BATMAN, see ya all!
Now, this is pretty wild. Not only would I never thought of doing this, but I would have never dreamed that it would have worked. What does the bios say about the processors? Are you running the regular or performance heatsinks?
BIOS says Hello! Regular heatsinks, thanks.