Searched around on the net, and wasn\'t able to find an answer. Curious if anyone here has ever come across an explanation.

The CEll BE on the PS3 uses only 7 of the 8 spe\'s available. The 8th is \"disabled\" so as to improve the yield on the cpu\'s. And the os / hypervisor uses the 7th.

Question: Just how is the 8th spe \"disabled\"?

If the Cell BE actually has a defective spe, the answer is self-explanatory.

But, assuming that the Cell BE actually has 8 functional spe\'s. Then what?

Is a spe physically \"destroyed\"? Or is this something that can be done via software (hypervisor?)

If so, does that imply that there is some potential (software) method of \"re-activating\" an 8th spe that was \"turned off\" via software?

Going from 6 functional spe\'s to 7 would be an increase of ~ 16%?

I\'ve looked, and can\'t find these answers.

Also, is it true that Cell BE native speed is 4.0 GHz, but is \"downgraded\" to 3.2 GHz on the PS3?

Can anyone point me in the correct direction?


Only thing I have been able to find is this:

IBM Says It\'s Lucky to Get 10% to 20% Yields on Cell Processor

With Reeves\' statements, it appears as though Sony will be producing PlayStation 3 consoles with different Cell processors -- some with all eight cores operational and some with just seven. Reeves however does not believe that Sony will offer different pricing for the machines and only time will tell if there will be performance differences. Reeves says however that users will not see any differences in speed. \"The PlayStation 3 only uses seven of [the eight cores]. You\'d have a spare.\"

Hy, how much spe\'s are using other application like Folding (7 under sony os?) or YoYo (6 like ps3grid under linux?)?
Is possible to use the 7th spe not for hypervisor but for cruncing in the future?
Thanks