Feeds

Oh no! It's Intel FDIV time again!

Floating point errors back from the dead to haunt Chipzilla

  • alert
  • submit to reddit

Bridging the IT gap between rising business demands and ageing tools

As if it weren't enough that you can't buy Coppermine Pentium IIIs for love nor money, the latest list of erratanotbugs on the Intel Web site (over 60 and counting) includes one guaranteed to send a shiver down the spines of everyone at Satan Clara: "E56. It is possible that a negative sign bit may be incorrectly applied to the result of an x87 floating point operation if it is closely preceded by a Streaming SIMD Extensions (SSE) multiply operation... ...Implication: If this erratum occurs, the result of an x87 floating point instruction which should be positive will instead be negative." It is apparently possible for a BIOS mod to provide a workaround for the bug, but at the moment, any Coppermine could be doing its sums wrong. This is terribly embarrassing for Chipzilla, which still uses the original Pentium FDIV (floating point divide) fault to put a scare into new recruits and to remind employees of the inherent fallibility of man. It's not entirely clear whether this bug applies to Katmai as well as Coppermine cores. The original Pentiums were made into expensive keyrings after Intel refunded millions of dollars to users, so if you're lucky enough to have a Coppermine, maybe those nice folks at Intel are about to refund you the purchase price... The URL for the site where you can download the PDF is here. Intel adds: "Intel publishes Spec updates, listing Errata (all processors have errata) to end users and manufacturers. This errata was identified and a fix published some time ago." ®

Build a business case: developing custom apps

More from The Register

next story
BBC goes offline in MASSIVE COCKUP: Stephen Fry partly muzzled
Auntie tight-lipped as major outage rolls on
iPad? More like iFAD: We reveal why Apple ran off to IBM
But never fear fanbois, you're still lapping up iPhones, Macs
Nadella: Apps must run on ALL WINDOWS – PCs, slabs and mobes
Phone egg, meet desktop chicken - your mother
HP, Microsoft prove it again: Big Business doesn't create jobs
SMEs get lip service - what they need is dinner at the Club
ITC: Seagate and LSI can infringe Realtek patents because Realtek isn't in the US
Land of the (get off scot) free, when it's a foreign owner
Samsung threatens to cut ties with supplier over child labour allegations
Vows to uphold 'zero tolerance' policy on underage workers
Dude, you're getting a Dell – with BITCOIN: IT giant slurps cryptocash
1. Buy PC with Bitcoin. 2. Mine more coins. 3. Goto step 1
There's NOTHING on TV in Europe – American video DOMINATES
Even France's mega subsidies don't stop US content onslaught
You! Pirate! Stop pirating, or we shall admonish you politely. Repeatedly, if necessary
And we shall go about telling people you smell. No, not really
prev story

Whitepapers

Seven Steps to Software Security
Seven practical steps you can begin to take today to secure your applications and prevent the damages a successful cyber-attack can cause.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.