[rescue] Apple to ditch IBM, switch to Intel chips

Patrick Giagnocavo patrick at mail.zill.net
Mon Jun 20 09:58:06 CDT 2005

On Mon, Jun 20, 2005 at 08:40:17AM -0600, Barry Keeney wrote:
> On Sun, 19 Jun 2005, Patrick Giagnocavo wrote:
> > > How do you run a 24x7x365 fab at 110%? On a leap year you get an extra what, 
> > > .25% from the extra day (29 Feb)...
> > Lionel ^^^^^^^
> > 
> > Overtime/extra shifts.  Yes it seems like a funny way to represent it,
> > but that is how semiconductor manufacturers represent it, as a %-age
> > greater than 100.
>   I've got this info from friends and family who work at the
> local Intel fab's.....
>   Doesn't work that way. With a fab that runs 24x7, 350+ days a year, 
> every station has someone working it, the equipment is already running
> as fast as possible. 

It could be that we are conflating terms, here is an article from
"Electronic News" that shows what I am talking about:


The quote appears towards the bottom:

Foundries are reaching more than 100 percent utilization rate, said
Genda Hu, VP of marketing. The rate is now closer to 105 percent.

"We can squeeze 250,000 more wafers out by adding just 5 percent
capacity -- by just adding to our efficiency," he said.

Manufacturers can squeeze out those extra percentage points by
extending the cycle time or working around shifts, or moving equipment
around among fabs, Kin said.

So maybe they are talking about 

 (improved yield after tweaks) / (initial yield when fab was built) = number greater than 1.00

whereas the info you got was accurate - they run the fabs all the


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