Intel Core i7-8700K And Core i5-8400 Review: Coffee Lake - More Cores, Performance And Value

Name: Intel Core i7-8700K
Brand: Intel

by Marco Chiappetta — Thursday, October 05, 2017, 09:00 AM EDT

Performance Summary: The Intel Coffee Lake-based Core i7-8700K and Core i5-8400 both performed well throughout our testing. The additional pair of cores help propel them well ahead of their previous-generation counterparts in multi-threaded benchmarks and their higher-clocks and use of Intel’s latest-generation processor cores also help single-thread performance. The 6-core/12-thread Core i7-8700K offered the best single-threaded performance we have seen to-date and its multi-threaded performance is roughly on-par with the 8-core/16-thread Ryzen 7 1800X and 1700X processors. And the Core i5-8400 managed to outpace the Core i7-7700K on a couple of occasions. Power consumption – especially at idle – was nice and low and 5GHz overclocks with decent cooling should now be a regularity with a bit of tweaking.

Intel Core i7-8700K And Core i5-8400 Processors -- Find Them At Amazon

Although they are not based on a totally new architecture, the design choices Intel made with Coffee Lake and its 8th Generation Core processors completely re-shape the company’s mainstream CPU line-up and bring the heat to AMD’s Ryzen 3/5/7. Here is a breakdown of how the 8th Generation Core processors series stacks up:

Intel 8th Generation Core Series Processor Line-Up

For $359, the Core i7-8700K competes well against 8-core Ryzen 7 series processors in multi-threaded workloads thanks to its higher frequencies, but it does so while also offering markedly better single-threaded performance and lower idle power. And versus its previous-gen counterpart, the Core i7-7700K, there is no comparison – the Core i7-8700K is faster all-around, for a similar introductory price. All things considered, the Core i7-8700K makes a compelling case for itself – this is one heck of a nice processor.

Though it doesn’t support HyperThreading, the Core i5-8400 also offers multi-threaded performance in a completely different league versus previous-gen quad-core Core i5 products, thanks to its 6-core configuration. In fact, the $182 Core i5-8400 even managed to overtake the Core i7-7700K in a couple of spots. Its multi-threaded performance isn’t on par with 6-core/12-thread Ryzen processors, but performance is still strong in its segment.

We really like where Intel is going with the first 8th Generation Core series processors – more cores and more performance, without breaking the bank. That's good stuff in our book. If you were considering a desktop CPU upgrade for a mainstream system, your decision may have just gotten a whole lot harder.


Strong Multi-Thread Performance Killer Single-Thread Performance Relatively Low Power High Overclocks	Requires New Motherboards, Despite Using LGA1151 Socket Not All Unlocked

Tags: Intel, CPU, processor, coffee lake, core i5-8400, core-i7-8700k

Marco Chiappetta

Marco's interest in computing and technology dates all the way back to his early childhood. Even before being exposed to the Commodore P.E.T. and later the Commodore 64 in the early ‘80s, he was interested in electricity and electronics, and he still has the modded AFX cars and shop-worn soldering irons to prove it. Once he got his hands on his own Commodore 64, however, computing became Marco's passion. Throughout his academic and professional lives, Marco has worked with virtually every major platform from the TRS-80 and Amiga, to today's high end, multi-core servers. Over the years, he has worked in many fields related to technology and computing, including system design, assembly and sales, professional quality assurance testing, and technical writing. In addition to being the Managing Editor here at HotHardware for close to 15 years, Marco is also a freelance writer whose work has been published in a number of PC and technology related print publications and he is a regular fixture on HotHardware’s own Two and a Half Geeks webcast. - Contact: marco(at)hothardware(dot)com