Your browser does not fully support modern features. Please upgrade for a smoother experience.
Submitted Successfully!
Thank you for your contribution! You can also upload a video entry or images related to this topic. For video creation, please contact our Academic Video Service.
Version Summary Created by Modification Content Size Created at Operation
1 handwiki Vivi Li -- 1139 2022-11-04 01:36:43

Video Upload Options

We provide professional Academic Video Service to translate complex research into visually appealing presentations. Would you like to try it?
No, upload directly Yes
Cite
If you have any further questions, please contact Encyclopedia Editorial Office.
HandWiki. Pentium FDIV Bug. Encyclopedia. Available online: https://encyclopedia.pub/entry/32969 (accessed on 23 September 2026).
HandWiki. Pentium FDIV Bug. Encyclopedia. Available at: https://encyclopedia.pub/entry/32969. Accessed September 23, 2026.
HandWiki. "Pentium FDIV Bug" Encyclopedia, https://encyclopedia.pub/entry/32969 (accessed September 23, 2026).
HandWiki. (2022, November 04). Pentium FDIV Bug. In Encyclopedia. https://encyclopedia.pub/entry/32969
HandWiki. "Pentium FDIV Bug." Encyclopedia. Web. 04 November, 2022.
Pentium FDIV Bug
Edit
The content is sourced from: https://handwiki.org/wiki/Software:Pentium_FDIV_bug

The Pentium FDIV bug is a hardware bug affecting the floating point unit (FPU) of the early Intel Pentium processors. Because of the bug, the processor might return incorrect binary floating point results when dividing a number. The bug was discovered in 1994 by Professor Thomas R. Nicely at Lynchburg College. Intel attributed the error to missing entries in the lookup table used by the floating-point division circuitry. The severity of the FDIV bug is debated. Though rarely encountered by most users (Byte magazine estimated that 1 in 9 billion floating point divides with random parameters would produce inaccurate results), both the flaw and Intel's initial handling of the matter were heavily criticized by the tech community. In December 1994, Intel recalled the defective processors. In January 1995, Intel announced "a pre-tax charge of $475 million against earnings, ostensibly the total cost associated with replacement of the flawed processors."

floating-point division floating point fpu

References

  1. Tom R. Halfhill (March 1995). "An error in a lookup table created the infamous bug in Intel's latest processor" (– Scholar search). BYTE (March 1995). Archived from the original on February 9, 2006. https://web.archive.org/web/20060209005434/http://www.byte.com/art/9503/sec13/art1.htm. Retrieved 2006-12-19. 
  2. Nicely, Thomas (August 19, 2011). "Pentium FDIV flaw FAQ". http://www.trnicely.net/pentbug/pentbug.html. 
  3. Alexander Wolfe. "Intel fixes a Pentium FPU glitch". http://davefaq.com/Opinions/Stupid/Pentium.html#glitch. 
  4. "Intel adopts upon-request replacement policy on Pentium processors with floating point flaw; Will take Q4 charge against earnings". Business Wire. 1994-12-20. http://findarticles.com/p/articles/mi_m0EIN/is_1994_Dec_20/ai_15939945. Retrieved 2006-12-24. 
  5. "How many engineers does it take to change a lightbulb?". Boiledbeans. 20 April 2009. http://www.boiledbeans.net/2009/04/20/how-many-engineers-does-it-take-to-change-a-lightbulb/. Retrieved 10 November 2009. 
  6. "How number theory got the best of the Pentium chip". Science 267 (5195): 175. 1995-01-13. doi:10.1126/science.267.5195.175. PMID 17791336.  https://dx.doi.org/10.1126%2Fscience.267.5195.175
  7. "FDIV Replacement Program: Frequently asked questions". Intel. 2009-03-20. http://www.intel.com/support/processors/pentium/sb/CS-012748.htm. Retrieved 2009-11-10. 
  8. "Pentium FDIV bug - a Picture". Kansas University Institute for Policy and Social Research. 1994-11-30. http://www.ipsr.ku.edu/stafffil/hoyle/pentium_fdiv/. Retrieved 2010-11-03. 
  9. "Ivars Peterson's MathTrek: Pentium Bug Revisited". Mathematical Association of America. https://www.maa.org/mathland/mathland_5_12.html. 
  10. Slob, Arie. "Windows 95 Troubleshooting: How to Check for a Faulty Math Coprocessor". http://www.helpwithwindows.com/windows95/troub-58.html. 
  11. "Pentnt". Microsoft. September 11, 2009. https://technet.microsoft.com/en-us/library/bb490967.aspx. 
  12. https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/pentnt
More
©Text is available under the terms and conditions of the Creative Commons-Attribution ShareAlike (CC BY-SA) license; additional terms may apply. By using this site, you agree to the Terms and Conditions and Privacy Policy.
Upload a video for this entry
Information
Subjects: Others
Contributor MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to https://encyclopedia.pub/register :
HandWiki
View Times: 8.8K
Entry Collection: HandWiki
Revision: 1 time (View History)
Update Date: 04 Nov 2022
Table of Contents
    Notice
    You are not a member of the advisory board for this topic. If you want to update advisory board member profile, please contact office@encyclopedia.pub.
    OK
    Confirm
    Only members of the Encyclopedia advisory board for this topic are allowed to note entries. Would you like to become an advisory board member of the Encyclopedia?
    Yes
    No
    ${ textCharacter }/${ maxCharacter }
    Submit
    Cancel
    There is no comment~
    ${ textCharacter }/${ maxCharacter }
    Submit
    Cancel
    ${ selectedItem.replyTextCharacter }/${ selectedItem.replyMaxCharacter }
    Submit
    Cancel
    Confirm
    Are you sure to Delete?
    Yes No
    Academic Video Service
    Feedback