SIMPLE HAND TEST:
In the Microsoft windows calculator try 5506153/294911
Correct: 18.67055823621
Pentium: 18.66990719234
If you get the incorrect answer then you definitely have the bug. If
you get the correct answer then either you have the newer Pentium chip
with the bug corrected, or you have a calculator which is "Pentium
aware". "Pentium aware" software looks for and catches any incorrect
division result caused by the bug and recalculates the result using
some other method so you still get the right answer.
CPU ID PROGRAM:
The only sure way to determine if your CPU does or does not have the
FDIV flaw is to identify the CPU's family, model, and stepping, and
compare that against a list of ones known to have the bug. Pentium
chips have a special instruction, CPUID, which returns chip
identification information. Intel has an official program which uses
the CPUID instruction to identify CPU chips, including which ones have
the FDIV bug. The program is available at:
