how intel determine Chip speeds

[xpower]

just confusing question is this but realy one chip is looked by intel speed at 3ghz and other 3.4ghz. same fabrication and spec. looks like they just overclock 3ghz chip to 3.4ghz with grater number but same line spec and lock it to that speed...... so whats the reality behine this............................

[CrazyNutz]

The process of building up the cpu cores on the silicon wafer is not %100 perfect. So you will have a number of CPU cores per wafer that are not as good as the others.

The wafers are sliced up into individual CPU's and then tested, and binned.

Binning is where they determine if the CPU is good enough to run at say 3.4ghz reliably and stay within the defined TDP. If if does not make the grade it will be binned lower perhaps as a 3ghz part
Also they may find that one core, or part of the cache, etc.. is bad. This CPU may become a dual core, etc.

[andressergio]

to add some info

watch this video and u will see why not a chip is the same as other

http://www.youtube.com/watch?v=Q5paWn7bFg4

cheers !
Sergio

[xpower]

so its the cores not the wafers that used in process. like cores are not upto that task and thus speed reduction of cores.

[andressergio]

so its the cores not the wafers that used in process. like cores are not upto that task and thus speed reduction of cores.

each wafer receive the image of chips a lot of them and the process its perfect but as each wafer is treated there must be tiny dif in the amount of material, quality of silicon or whatever parameter may vary, silicon is from the same torpedo as u can see

[xpower]

i still dont believe intel can put billions of transistors on each core. the fact so tiny cores doubt it.......