Hi..
 > Get a program called AsmEdit, filename: AEDT184.ZIP.
 > From said program's (extensive) online help:
 >  Pentium + only instructions Ü
 >   ßßßßßßßßßßßßßßßßßßßßßßßßßßßßß
 > The following instructions are only implemented on 80586+:
 >  RSM
RSM is available on any intel SL Enhanced CPU, including the 486 and 386 
examples.... it is part of power management, NOT a general purpose 
new-to-pentium instruction.
 > All MMXÿInstructions will only be available on 80686, too.
There already exists in the marketplace pentim-mmx (80586, if you like), as 
well as pentium-pro-mmx.
Sounds like your "guide" is a little out of date?
    Craig
--- FMail/386 1.20
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