In article <1993Jan25.170138.10928 at welchgate.welch.jhu.edu>, ken at oscar.welch.jhu.edu (Ken Fasman) writes:
|> My understanding of the various members of the Intel 80386 and 80486 families
|> are as follows:
|>|> Chip Internal External Floating
|> Designation Data Path Data Path Point Unit?
|> ----------- --------- --------- -----------
|> 386DX 32 bits 32 bits No
|> 386SX 32 bits 16 bits No
|>|> 486DX 32 bits 32 bits Yes
|> 486SX 32 bits 16 bits Yes
|>|> Please note that Intel uses the "SX" designation to denote the narrower
|> external data path, NOT the presence or absence of a math coprocessor.
This is not quite right! It turns out that the 486SX had its floating point
unit disabled in the original chip, and removed from the die altogether in
later versions. That is, the 486SX has a 32 bit internal data path, a 16 bit
external data path, and NO FLOATING POINT COPROCESSOR.
Thanks to Ray Duncan and Peter Li for pointing out the error of my ways. :-(