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infamous bugs?

By Medusa2 ·
Pentium CPU has the infamous FPU (co-processor) bug.
Is there a fix for this?

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infamous bugs?

by TheChas In reply to infamous bugs?

It has been so long since I have seen the patch posted, I don't know if it is still out there.

I found a couple of pages at Intel's site with some information;

http://www.intel.com/support/processors/pentium/fdiv/index.htm

http://www.intel.com/support/processors/pentium/software.htm

Remove any spaces from the pasted links.

Intel still has the DOS version of the utility, and per the inforamtion, it only affects 60 - 100 MHz CPUs.

Chas

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infamous bugs?

by Medusa2 In reply to infamous bugs?

The question was auto-closed by TechRepublic

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infamous bugs?

by maxwell edison In reply to infamous bugs?

The “Bug”

This bug occurs with operations that convert floating-point numbers into integers. Floating-point numbers are stored in an 80-bit format, while integers are stored in 16-bits (for short integer) and 32-bits (for long integers). Sometimes, converting an 80-bit floating-point number into an integer on the Pentium II and the Pentium Pro produces the Dan-0411 bug. This happens when the converted floating-point number won't fit into the smaller integer format. According to Intel's Flag Erratum Technical Description site, the erratum occurs only when the FIST[P] instruction is either a 16- or 32-bit operation; either the 'to nearest', 'to zero' or 'up' rounding modes are being used; the sign bit of the floating-point operand is negative; and the floating-point operand being converted is significantly more negative than can be described by the integer size being targeted.


The “Fix”

"It's available to [dealers and PC makers] only via Intel's private Web site for resellers. It is not currently available to the end consumer," one customer told CNET's NEWS.COM. Companies must first receive special "training" before getting access to the privileged bug-fixing site.


The Odds:

The chanceof this bug occurring is 1 in 8.6 billion, when storing 16-bit integers, and 1 in 562,950 billion, when storing 32-bit integers.


Related Sites:

http://www.cs.earlham.edu/~dusko/cs63/fpu.html

http://news.com.com/2100-1001-205144.html?legacy=cnet


Conclusion:

Have you bought a lottery ticket lately?


Maxwell

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infamous bugs?

by Medusa2 In reply to infamous bugs?

The question was auto-closed by TechRepublic

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infamous bugs?

by Medusa2 In reply to infamous bugs?

This question was auto closed due to inactivity

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