Let's keep this short and sweet. If you're building a new PC, you want an Intel CPU. Intel's 14-nm Skylake chips are the best performers on the market by almost any measure, and it's been that way for quite some time now. We won't rehash the reasons for why this is here—go read our Core i7-6700K review for all the details. Skylake chips offer small-but-welcome increases in performance over Haswell parts pretty much across the board, and the high-end Z170 chipset offers more PCI Express lanes for next-generation storage and high-speed I/O ports than Intel's 9-series boards. Given these advantages, we'd generally recommend building around a Skylake processor if possible.
While most consumers will be interested in Skylake chips, Intel's launch of its Broadwell-E CPUs is the largest change in the CPU market since we last published a System Guide. That range of chips tops out with the seriously impressive 10-core, 20-thread Core i7-6950X.
The Broadwell architecture alone is only an evolutionary improvement over Haswell before it, but Intel has compensated for the single-threaded performance gap between Broadwell and Skylake CPUs with a new technology called Turbo Boost Max 3.0, or TBM3 for short. To make this technology work, Intel finds the core with the highest performance potential on each Broadwell-E CPU die during production, and a companion Windows driver prioritizes work to run on that core. On the Core i7-6950X in our labs, that means the best-performing core on the chip can boost up to 4GHz. At those speeds, a single-threaded Broadwell-E workload (namely, Cinebench) trails a Haswell Core i7-4790K by only 6%. The Core i7-6700K is only about 3% faster than the Core i7-4790K, so if you need all of Broadwell-E's cores, you can mostly have your cake and eat it, too.
Broadwell-E's problem—if it can be called that—is that Intel has decided to establish a new pricing tier for the top-end chip in the lineup instead of pushing up the core counts for the same price, as it has in its past generations of high-end desktop CPUs. The Core i7-6950X sells for $1750 right now, not a small gap over the eight-core, 16-thread Core i7-6900K and its $1099 price tag. Consider the fact that you can build a complete (and very nice) Core i7-6700K PC for just a little more than this CPU alone costs, for perspective. We've never recommended the top-end Intel Extreme CPUs to begin with, and the Core i7-6900K and Core i7-6950X don't do anything to change that. Unless you're certain your workload can take advantage of all the resources the Core i7-6950X has to offer, we think most can safely forget about it.
Intel's Broadwell Core i7-5775C still deserves a mention here for folks after a taste of the exotic. This CPU is unique among Intel's desktop offerings because of its 128MB of eDRAM, a resource that the i7-5775C can use as a large last-level cache. In our testing, we found that the 5775C appears to have a natural advantage in producing low frame times in games. This CPU is a bit of an odd bird, though. It relies on the older Z97 platform and DDR3 RAM, and its high cost—about $50 more than Intel's own Core i7-6700K—makes it a hard sell unless you're quite serious about getting the lowest frame times around, or you want the chip's powerful integrated graphics. We've discussed how to build around this CPU in several past Guides, so we won't repeat those recommendations here.
Despite our preference for Intel CPUs, AMD’s Athlon X4 880K is getting a home in our budget recommendations. This $95 quad-core CPU is basically a high-end Godavari APU with its onboard graphics disabled. While the 880K won’t be able to match our favorite Intel Core i3-6100 in single-threaded workloads, it ships with a high-quality stock cooler and an unlocked multiplier. That means builders on a budget might be able to close the gap with the Core i3-6100 a bit. We've tested AMD’s Wraith cooler, a fancier version of the one that ships with the X4 880K, and we've found that it offers performance similar to some smaller aftermarket heatsinks. Not bad for something that comes in the box.
|AMD Athlon X4 880K||$94.12||AMD Socket FM2+ motherboard|
|Intel Core i3-6100||$124.99||Intel LGA1151 motherboard|
In this price range, we think Intel’s Core i3-6100 is a great buy. Its healthy 3.7GHz clock speed should be brisk enough for most, and its Hyper-Threading support can boost performance in multithreaded tasks. It’ll also appear as a quad-core CPU to games that require one. This Core i3 is a good choice for non-gamers, too, since it has basic integrated graphics. For $125, it's hard to find anything to complain about with this chip.
For those who want to tinker with clock speeds on a budget—or for folks whose budgets just don't stretch to the Core i3-6100—AMD’s Athlon X4 880K gets a conditional nod from us. Since the X4 880K is a quad-core CPU, it should also work with most modern games without a hitch. The 880K won't be as fast as the Core i3-6100 in single-threaded workloads, though, and overclocking it probably won't close the gap that much. Still, AMD's beefy stock cooler should allow budget builders to turn up the clocks without spending extra for an aftermarket cooler, and that could be an attractive value proposition for an entry-level system.
|Intel Core i5-6500||$204.99||Intel LGA1151 motherboard|
|Intel Core i5-6600K||$244.99||Intel LGA1151 motherboard, Z170 chipset for overclocking,
aftermarket CPU cooler
|Intel Core i7-6700K||$359.99|
Moving up to our sweet-spot picks gets builders into Intel’s quad-core CPUs. If you don’t want to get into overclocking, the Core i5-6500 looks like the Goldilocks chip in this price range. For about $205, the i5-6500 gives us 3.2GHz base and 3.6GHz turbo clocks in a miserly 65W thermal envelope. The Core i5-6500 is also a great CPU for a VR-ready machine. As a warning, we aren’t as enamored of the Core i5-6400. Though it sells for $15 less than the i5-6500, the i5-6400 pays for it with a big drop in clock speeds. We don't think the step down to 2.7GHz base and 3.3GHz Turbo speeds is worth the savings.
The logical step up from the Core i5-6500 is Intel’s Core i5-6600K. This part gives us four cores running at 3.5GHz base and 3.9GHz Turbo speeds, along with an unlocked multiplier that gives overclockers free rein. From there, the beastly Core i7-6700K adds Hyper-Threading and turns the clocks all the way up to 4GHz base and 4.2GHz Turbo speeds. Overclockers are free to explore the i7-6700K's upper limits, too.
Since Intel doesn't include a stock cooler with its K-series CPUs any longer, be sure to grab an aftermarket cooler from our selections later in this guide if you're building with a Core i5-6600K or a Core i7-6700K—and make sure it's a beefy one if you're choosing the i7-6700K. Our experience with that chip has shown that it's quite the challenge to cool, even for large tower heatsinks.
If the Z170 platform doesn't offer enough PCIe lanes, memory bandwidth, or memory capacity for your needs, Intel's "Extreme" CPUs and X99 motherboards are the next step up for desktop PCs.
|Intel Core i7-6800K||$439.99||LGA2011-v3 motherboard,
quad-channel DDR4 memory kit,
discrete graphics, aftermarket cooler
|Intel Core i7-6850K||$649.99|
With the advent of Broadwell-E, we think the best CPU choice in the lineup is probably the Core i7-6850K. At a moderate premium over the Core i7-5930K, this chip offers Turbo Boost Max 3.0 support alongside six cores and 12 threads of processing power. Its 15MB of L3 cache and support for up to 128GB of DDR4-2400 RAM are nice steps up over Intel's high-end quad-core chips. As a minor bonus, this chip also runs at slightly higher clock speeds than the $1099, eight-core Core i7-6900K. Like all Broadwell-E chips, the Core i7-6850K is unlocked for easy overclocking.
If you want extra cores and threads, and you don't need all 40 of the PCIe 3.0 lanes from fancier Broadwell-E chips, the Core i7-6800K and its 28 lanes of PCIe 3.0 connectivity fill the same role the hobbled Core i7-5820K did with Haswell-E. Even considering Nvidia's move to officially support two-way SLI only with its Pascal graphics cards, the Core i7-6800K comes up a little short for folks planning multi-GPU setups. Considering that limitation, we'll continue to conditionally recommend this chip for folks who are absolutely sure they won't miss the extra lanes.