i had always assumed they performance tested the cpus after a production run and sorted them by performance. ones with higher ratings were sold at the premium end, and once that scored lower were downclocked and sold as the economy end. i know nvidia did something like this with their g92 line of gpus.
In some ways, they do. A few facts...
1) Unmoving inventory is a waste of money. Don't store up your inventory for a rainy day--it'll spoil.
2) One silicon crystal 300mm wide can yield hundreds or more slivers and can yield thousands of processors in total.
3) General rule of thumb: keep enough stock on hand to make/get more. Turning over your inventory every 2 weeks is very good if you can control manufacturing.
4) What Intel does is bin the processors. They first sort out functional versus flawed processors, and then test the flawed processors to see if they're salvageable (ie: L2 cache flaw mean a lower-end processor, L1 cache flaw or CPU core flaw may mean a processor with disabled cores). If they're not, they're disposed of.
5) Intel builds what is ordered. For an older example we'll use the Conroe core (original C2D). Conroe came in a large range of CPUs--Celeron
[email protected] to the Core 2 Extreme
[email protected]. Any chip that had an unusable CPU core or majorly flawed L2 cache will be marked at the Conroe-L (Celeron 420, for example). Any with 2 functional cores but was not capable of higher clock-speeds was binned either as Celeron or as C2D E6300 @ 1.86GHz. And so on--the best chips aren't necessarily the Extreme Edition processors, though they are the quickly-IDed chips that will do high clocks with low voltages.
6) In tech especially, large inventory is bad. Things go obsolete quickly and prices often change. Intel, for example, had updated Conroe many times.
