right - fewer slow chips as process matures
You might very well be correct.
IBM (or any other CPU manufacturer) doesn't set out to make a "1.6" chip as something different from a "1.8" chip. There's only one manufacturing process. (Within a line, of course. The PPC970 and PPC970fx are obviously different.)
All the chips go through the same process, and come on the same wafers. After the chips are made, they are tested and ranked by the fastest speed that they will reliably run. You might find that a 2.5GHz chip came from right beside a 1.6 GHz chip on the same wafer (and beside a dead chip too).
That being said, as the process matures the chips get better - you find more chips in the "fast" bins and fewer in the "slow" and "dead" bins.
Therefore, a chip sold as "slow" could easily be capable of running faster - the chip might be under-clocked in order to meet the demand for slower chips.
____________________________________
Therefore, should IBM take a "fast" chip, mark it as "slow", and sell it for less money? Doesn't make financial sense for IBM if the fast chips are in short supply - especially since the cost per chip is the same for IBM.
Therefore, would Apple want to sell fewer higher-margin "fast" machines in order to sell more lower-margin "slow" machines? Doesn't make sense for Apple if the fast chips are in short supply.
Only when the demand for fast chips is met will it be advantageous to under-clock the chips.
grantozolins said:I'd bet you anything the 1.6 is just an underclocked 1.8 off the same line. Which would explain why the popularity of the G5 Imac could be putting constraints on the supply of lower clocked G5s.
You might very well be correct.
IBM (or any other CPU manufacturer) doesn't set out to make a "1.6" chip as something different from a "1.8" chip. There's only one manufacturing process. (Within a line, of course. The PPC970 and PPC970fx are obviously different.)
All the chips go through the same process, and come on the same wafers. After the chips are made, they are tested and ranked by the fastest speed that they will reliably run. You might find that a 2.5GHz chip came from right beside a 1.6 GHz chip on the same wafer (and beside a dead chip too).
That being said, as the process matures the chips get better - you find more chips in the "fast" bins and fewer in the "slow" and "dead" bins.
Therefore, a chip sold as "slow" could easily be capable of running faster - the chip might be under-clocked in order to meet the demand for slower chips.
____________________________________
Therefore, should IBM take a "fast" chip, mark it as "slow", and sell it for less money? Doesn't make financial sense for IBM if the fast chips are in short supply - especially since the cost per chip is the same for IBM.
Therefore, would Apple want to sell fewer higher-margin "fast" machines in order to sell more lower-margin "slow" machines? Doesn't make sense for Apple if the fast chips are in short supply.
Only when the demand for fast chips is met will it be advantageous to under-clock the chips.