Intel's previous generation processors, code named Kaby Lake, weren't much of an improvement on the desktop side compared to Skylake before it. In fact, Kaby Lake desktop CPUs were essentially factory overclocked Skylake chips. Now Intel is introducing the latest generation of their Core processors for desktops, Coffee Lake, featuring more cores and launching October 5th.
Leading the pack of these new processors is of course the i7-8700K (bulk order price: $359). The new flagship i7 now has 6 cores and 12 threads, up from the 4/8 it's been for many years. It's now a 95W TDP part, but even with a 4W TDP bump Intel had to make another trade off for the additional cores by dropping the base clock to 3.7GHz from the 4.2GHz of the i7-7700K. The new i7 is able to boost up to 4.7GHz, and has 12MB of L3 cache. Intel claims it'll provide up to 25% more frames per second in games compared to the 7700K, and be up to 2x faster than a three year old PC (so Broadwell) when "mega-tasking" (gaming+streaming+recording). The non-overclockable 65W i7-8700 ($303) is a little slower with a base clock of 3.2GHz and a boost of 4.6GHz.
The mid-range i5-8600K ($257) is also getting two more cores, bringing it up to 6, but still lacks hyperthreading. Base clock speed drops only 200MHz from Kaby Lake, now 3.6GHz and boosts up to 4.3GHz. This 95W CPU as well as the 65W i5-8400 ($182) have 9MB of cache. The later's clock speed is much slower at only 2.8GHz base frequency and a 4GHz boost.
The i3-8350K ($168) might be the most interesting of them all, believe it or not. This desktop i3 part now has 4 cores and a clock speed of 4GHz. It doesn't have Intel's Turbo Boost feature, nor is it hyperthreaded like its Kaby Lake predecessor. That being said, 4 cores at 4GHz is just right for playing AAA games at higher settings these days. With a 91W TDP and being unlocked by Intel, it should overclock decently for anyone that wants to squeeze out a little more power. The i3-8100 ($117) 65W variant's clock speed it locked at 3.6GHz, and both i3s have 6MB of cache.
These Coffee Lake CPUs are still on Intel's 14nm node, the fourth generation at this size. Intel has referred to both Kaby Lake and now Coffee Lake as "optimization" releases, or 14nm+ and 14nm++ for short. With slower clock speeds and a largely unchanged integrated GPU, at first glance Coffee Lake seems like Skylake cores with Kaby Lake's iGPU, albeit with additional cores.
They utilize the same 1151 socket as Skylake and Kaby Lake, but this is Intel so Coffee Lake also uses their new Z370 motherboard chipset. Intel claims this new chipset is required for proper power delivery with the increased number of cores, among other things. Kaby Lake CPUs work on some Z170 motherboards with an update, so many will find Intel's reasons hard to believe.
The top new CPUs are a little more expensive as well. The prices announced are for bulk orders of 1000 units. With that in mind, the new i7-8700K bulk price is $20 more than the the previous release, so expect a retail price closer to $400 for Intel's latest and greatest consumer CPU. The i5-8600K is similarly $15 more than the previous iteration. The rest of the lineup is about on par with previous generations.
A higher price tag and the need for yet another new motherboard may be acceptable for those that will benefit from more cores and more threads. However, Intel is no longer the sole supplier of high end CPUs for consumers and enthusiasts that are worth buying. AMD's Ryzen line delivers more cores that perform well for a reasonable price.
If we compare by similar pricing, the new i7 is pitted against AMD's 1700X at the $400 range. Intel's offering will almost definitely perform better in single threaded applications as its base frequency alone is 300MHz faster than the AMD chip. On the other hand, if you're looking for more cores the 1700X has 8 of them with 16 threads. If you want to save about $70 and are willing to overclock, you could also opt for the 65W TDP Ryzen 7 1700.
With a retail price of $250, the Ryzen 5 1600X should be a little cheaper than the i5-8600K once it goes on sale. Both have a base frequency of 3.6GHz, and the 1600X boosts to 4.0GHz while the 8600K is able to go to 4.3GHz. Once again, the Intel offering at this price point will likely edge out in single threaded performance. However, even though both have six cores, the 1600X uses AMD's simultaneous multithreading to have 12 threads.
At the sub-$200 price point the competition is very interesting now with Intel's new Coffee Lake CPU. If we compare by configurations the i3-8350K goes up against the Ryzen 3 1300X. The later is 500MHz slower, but can boost up to 3.7GHz. More importantly, it should be at least $40 cheaper than the Coffee Lake i3. That's a significant amount for anyone making a budget build. The i3 will perform better with single threaded applications in this matchup. For a similarly priced processor, the 8350K will likely go against the Ryzen 5 1400 or 1500X. With only a $20 difference between them there's little reason to not go with the 1500X, as it has double the L3 cache at 16MB and can boost up to 3.9GHz. Either way, both of these processors are multithreaded while the i3 is not.
Intel's Coffee Lake CPUs close the gap with AMD's Ryzen for multithreaded workloads. Even though the new generation of Core processors are slower compared to Kaby Lake out of the box, they'll very likely still retain the lead over Ryzen when it comes to single threaded applications as well. But AMD still offers more cores/threads if that's something you need, and AMD also intends to support their new AM4 platform until 2020. If you invest in Ryzen now and want to upgrade in a few years you won't be required to buy a new motherboard (and potentially RAM as well) like you are with Intel. It's said competition is always a good thing, and AMD's Ryzen has forced Intel to make the biggest change to their desktop lineup since Sandy Bridge. Here's hoping it lasts for many more years.