There is absolutely no doubt that some systems will run slower with
MPE/iX 5.0.  This is because HP chose not to compile code to the lowest
common denominator PA-Risc hardware.
 
Specifically 9x7 class machines will generally see no performance
gains/losses, while the older systems should see 10-15% slower execution
on certain applications...
 
I have the specifics on what programs, percentage losses, etc... but I
guess that anybody with the older hardware already knows this
information, and anybody with the new hardware doesn't need it anyway.
 
Happy new year
 
David