HP-41CL Speed test vs. DM41X and DM42

[grsbanks]

Absolutely, I do know that the speed increase is not linear and that TURBO50 will not make programs run 5× faster than TURBO10. That's not what puzzled me.

What puzzled me is the difference in relative speeds for the two machines.

For the first test, a DM41X on USB power completes it in more or less the same time as a 41CL running in TURBO50 mode (35ms per iteration vs. 40ms). For the second test, the DM41X on USB power is 3× faster than a 41CL in TURBO50 mode.

The stopwatch is used in the same way for both tests.

Neither test uses any instructions from a physical module (so no i/o on the expansion bus is needed).