While Intel's naming scheme for its processors is often best described as "obtuse," there have been some patterns that the company seemed to follow. For desktop processors, the i7 branding denotes chips with hyperthreading enabled, running two threads on each core. i5-branded parts had the same number of cores but with hyperthreading disabled. i3 parts in turn had fewer cores than i5 parts, but once again with hyperthreading enabled. The 8th generation chips changed this pattern a little—the desktop i3s don't have hyperthreading, just fewer cores—but the relationship between the i5s and i7s remained.
It looks like the next batch of Intel processors, probably branded 9th generation, is going to shake this situation up further. Benchmarks found in the SiSoft Sandra database list a Core i7-9700K processor. This increases the core count from the current six cores in the 8th generation Coffee Lake parts to eight cores, but, even though it's an i7 chip, it doesn't appear to have hyperthreading available. Its base clock speed is 3.6GHz, peak turbo is 4.9GHz, and it has 12MB cache. The price is expected to be around the same $350 level as the current top-end i7s.
For the chip that will sit above the i7-9700K in the product lineup, Intel is extending the use of its i9 branding, initially reserved for the X-series High-End Desktop Platform. The i9-9900K will be an eight-core, 16-thread processor. This bumps the cache up to 16MB and the peak turbo up to 5GHz—and the price up to an expected $450.
Below the i7s will be i5s with six cores and six threads and below them, i3s with four cores and four threads.
Even without hyperthreading, the new i7s should be faster than old i7s. A part with eight cores is going to be faster than the four-core/eight-thread chips of a couple of generations ago and should in general also be faster than the six-core/12-thread 8th generation chips. Peak clock speeds are pushed slightly higher than they were for the 8th generation chips, too.
Nonetheless, this change in branding does suggest that Intel is running out of room to maneuver. The 6th, 7th, 8th, and imminent 9th generation processors all (except for some rare 8th generation parts) use cores that are close derivatives of the Skylake design, with each new generation bumping up clock speeds and core counts a little. But both appear to be near their limits. The clock speed changes amount to a mostly negligible 100 or 200MHz, and increasing core counts is of limited value, too. The utility of the extra cores (or threads) is greatly diminished for most mainstream users, and, while Intel does have designs with more than eight cores, these are Skylake-SP and Skylake-X parts; they use a different socket, they have a very different internal layout (the cores are arranged into a grid rather than a ring), and they don't include an integrated GPU.
Intel's 10nm manufacturing process and future core designs may be able to create a bigger generational improvement, but the latter depend on the former, and the former isn't expected to go into mainstream production until some time next year.
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Ars Technica
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