One fast but awkward chip

Intel Core i7-7740X.

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Intel Core i7-7740X.

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One of the best gaming CPUs you can get, except there’s another CPU just like it.

The Intel Core i7- 7740X is Intel’s first quad-core high-end desktop processor, and it’s also priced to match the asking price of the mainstream Core i7-7700K.

This was interesting for many reasons, but it was also puzzling. Thanks to Kaby Lake-X, Intel’s enthusiast platform is now more accessible than ever, which is good news, but that also begs the question – who are these chips for?

In fact, other than the far larger package size, it can be thought of as a Core i7- 7700K with modest changes.

Clock speeds have been bumped up to 4.3GHz, a 100MHz increase, but Turbo Boost speeds and cache sizes are unchanged. However, memory support has been extended to include up to DDR4-2666, compared to DDR4-2400 on the Kaby Lake part.

The TDP now sits at 112W, up from 91W on the Core i7-7700K. This unfortunately isn’t a product of some under-the-hood boost in processing power, and the underlying architecture is still the same as its Kaby Lake sibling. This means the chip also doesn’t benefit from the new Turbo Boost Max Technology 3.0 or the rejigged cache hierarchies on Skylake-X.

Intel also chose to disable the HD Graphics 630 iGPU that’s still physically present on the chip. This effectively gets rid of many features that could appeal to mainstream consumers, such as native HEVC encode and decode. You could argue that enthusiasts wouldn’t miss these features, but it’s also a bit of a stretch for a so-called enthusiast to settle for a quad-core processor.

Performance is extremely similar to that of the Core i7-7700K, and this confusing situation is compounded by the fact that you get literally zero features for picking Intel X299 over Z270. The Kaby Lake-X chip has the same 16 PCIe 3.0 lane as the Core i7-7700K, so many of the features on an X299 board would be disabled.

Yes, there’s now a clear upgrade path to a 10-core Skylake-X CPU, but that’s about the biggest reason to go with Kaby Lake-X that we can think of. The Core i7- 7740X does overclock better than the Core i7-7700K, but that hardly seems like a major factor that will sway a large number of potential customers.

The chip works with the new LGA
2066 socket.
The chip works with the new LGA 2066 socket.



MEMORY SUPPORT Dual-channel DDR4- 2666.


TDP 112W.


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