Why do all i5 and i7 have same transistor count?

[The Tiger]

1400 million - the magic number! My laptop's i7 3610qm, desktop's i5 3570, as well as my friend's laptop's i5 3210M - all have 1400 million transistors.
According to GPU-z.

How is this possible? They have different speeds, i7 is hyperthreaded vs i5, still why they all have the same number of transistors?

Then why the huge price difference between i5 and i7?

Do i3 also have 1400 million transistors?

 

[mauller07]

most likely just the wrong information being displayed, the i7's would have the highest number of transistors due to larger l3 cache and hyperthreading support. i3 the least.

 

[rgd1101]

GPU-z probably didn't count it right. :lol:

 

[Sakkura]

Most of them come from the same fab. They just deactivate certain functions on different CPUs. Even so far as deactivating entire cores. In some cases in the past, it was actually possible to reactivate those cores, but they've learned from that - now they usually laser damage the deactivated cores so that trick doesn't work.

 

[Sakkura]

most likely just the wrong information being displayed, the i7's would have the highest number of transistors due to larger l3 cache and hyperthreading support. i3 the least.

The transistors for hyperthreading and so on are still present in the Core i5s, they're just deactivated.

 

[The Tiger]

Most of them come from the same fab. They just deactivate certain functions on different CPUs. Even so far as deactivating entire cores. In some cases in the past, it was actually possible to reactivate those cores, but they've learned from that - now they usually laser damage the deactivated cores so that trick doesn't work.

Really? Gee! Why do they cut and waste more money like this? Why don't they simply make different chips with fewer transistors?

 

[mauller07]

the fabrication process is not 100% efficient which is why there are so many different models and speeds of processors.

the highest end models are often the most expensive also because they are essentially the best binned chips that are mostly flawless.

 

[cklaubur]

Most of them come from the same fab. They just deactivate certain functions on different CPUs. Even so far as deactivating entire cores. In some cases in the past, it was actually possible to reactivate those cores, but they've learned from that - now they usually laser damage the deactivated cores so that trick doesn't work.

Really? Gee! Why do they cut and waste more money like this? Why don't they simply make different chips with fewer transistors?

Sometimes during testing, a chip won't run at certain settings correctly (defective cores, bad cache, etc), but fine at lower settings. Rather than throw an otherwise good chip away, they will sell it as a lower level chip. It actually saves them money.

Casey

 

[rgd1101]

Most of them come from the same fab. They just deactivate certain functions on different CPUs. Even so far as deactivating entire cores. In some cases in the past, it was actually possible to reactivate those cores, but they've learned from that - now they usually laser damage the deactivated cores so that trick doesn't work.

Really? Gee! Why do they cut and waste more money like this? Why don't they simply make different chips with fewer transistors?

Sometimes during testing, a chip won't run at certain settings correctly (defective cores, bad cache, etc), but fine at lower settings. Rather than throw an otherwise good chip away, they will sell it as a lower level chip. It actually saves them money.

Casey

it also save them money by not designing another chip with all the develop/testing/qa and other stuff.

 

[The Tiger]

Thank you, thank you very much, everyone for the answers!