Motorola and Apple. 4 years of disappointment, a follow up [update]
[Update] We were advised to rub our figures, which we did, keeping only overall values.
The previous news about Motorola CPU unit's disappointments drew an impressive amount of reactions. Before going further on this chapter, we wish to state we hold no personal grief against that company, which has brought to the general public so many important devices. Therefore, one must realize that their CPU business unit, which produces theG4 chips, hasn't been successful in keeping to the success of the other units.
We received very interesting information on IBM and Motorola chip production results, which we must say no-one can confirm for us. First, some information to remind you how chips are produced.
This production is very much like a photographic development, except the support is a wafer. This wafer is a circular board of different sizes depending on production site. Over this board, light is cast through a mask. This mask holds the drawing of the CPU and all its circuits, and during this insulation process, some places will receive light while some others won't. By a process similar the one used to develop photo, the places that received no light are wiped off so that a CPU emerges. Many CPUs simultaneously produced from a single wafer.
Like in every production process, success rate and quality are very diverse, and know how is crucial. The thinner the engraving, the faster the CPU will run. This means a tenth of a thousandth millimetre error margin! Chips from a wafer are then tested to a certain frequency, for which they'll be certified for, or else they'll be dumped.
Therefore here are some very recent results observed by IBM & Motorola:
Both IBM & Motorola divide their chips in 3 categories according to the frequency they can use. The best are P, then come L and N categories.
On a 12" wafer, IBM simultaneously produces 105 PPC 970. The certified CPU rate is high.
Almost 80% of certified CPUs reach 1.6 to 2 GHz, those ones will be found in our computers.
A small number in the P category even reaches or goes over 2.5 GHz.
As there are so few of them, P category isn't used by Apple though, which is also the case for N.
On a wafer, Motorola simultaneously produce 98 G4 PPC 7457. There's a problem though. Out of these 98, only a very little quantity is usable, around one fifth of IBM results.
According to our sources this would be the explanation of the new Powerbook delay. To end up with it, we'll let you know that when Motorola eventually dropped its G5 project, their engraving results were from 1.2% to 0.8% for the N category, and 0.4% for L (there was no P category).
[Transl. Kalomir]