There are a number of things you can do to improve the "effective" speed of an HP48 series calculator. I would recommend installing a faster stack replacement, such as those I've written, Java or HPSauce.
This not only provides additional user features such as on-screen algebraics, but also improves the general "feel" when using the stack interface.
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This not only provides additional user features such as on-screen algebraics, but also improves the general "feel" when using the stack interface.
See also the FAQ for more information.