Need old Pentium PC with FDIV bug

[ford]

Hi - I'm doing some research that would benefit from being able to test on an old PC containing a Pentium CPU with the infamous FDIV bug. I think we're talking about a 1994-ish PC, but the processor _must_ contain the FDIV bug. (I need a working PC, not just the CPU itself, although if I could get an "FDIV bugged" CPU and a compatible motherboard separately that might be an option.) Any pointers to a potential source would be much appreciated.

Thanks,
Bryan

 

[IBMMuseum]

Hi - I'm doing some research that would benefit from being able to test on an old PC containing a Pentium CPU with the infamous FDIV bug. I think we're talking about a 1994-ish PC, but the processor _must_ contain the FDIV bug. (I need a working PC, not just the CPU itself, although if I could get an "FDIV bugged" CPU and a compatible motherboard separately that might be an option.) Any pointers to a potential source would be much appreciated.

You would need any of the listed S-spec FDIV CPUs, and a system (Socket 4 or Socket 5, as appropriate) able to run one of them...

Please note, that despite the "Pentium Overdrive for 486" (Socket 3 CPUs) having much the same steppings (B1, B2, C0) and release dates as the FDIV CPUs, those models did not have the FDIV bug. S-specs on them are:

SZ953: 63MHz, B1 step
SZ990: 63MHz, B2 step
SU013: 63MHz, C0 step
SU014: 83MHz, C0 step

They have separate 8Kb code and data L1 caches, and are clocked at a 2.5 multiplier from the base frequency (thus 25 or 33MHz motherboard).