And you don't have any other FlightSim peripherals connected to the offending Computer that could cause a conflict with the Joystick in question? Something is causing your Sim to impart Input to the Rudder; a misassigned Axis, conflicting entries with Sensitivities... something. The Wingman works on the Dell (but 'slow'?) and not at all with the Acer. I don't know what "prefetch" is but since the Rudder issue is still there it's not the fault of that add on. It could also be the twist axis Pot is bad and doesn't present itself on the Dell but does on the Acer.
Just trying to eliminate the Variables short of a 'click to Restore Defaults' or a complete Re-install. Compare the Joystick properties in Sim between the Dell and the Acer, and see if it's the same. Also check the Realism Settings between them regarding P factor, Torque, etc.
I'm spitballing here throwing things out...