Introduction

Today, we bring you our Core i7-10700K review. This is the processor reviewers weren't sent samples for; instead, Intel sent the 10-core flagship Core i9-10900K and the performance-segment Core i5-10600K. The Core i7-10700K comes in at $380–$400 and is an 8-core/16-thread processor, having pretty much the same chops as the Core i9-9990K, the previous-generation flagship. Thanks to Intel enabling HyperThreading across the lineup with the 10th Gen Core "Comet Lake" desktop processor family, you now get 20 threads around the $500-mark with the Core i9 series, 16 threads for $350–$400 with Core i7, 12 threads with the wide-ranging Core i5 series priced between $160–$290, and 8 threads with Core i3 for $120–$150.

This is in fact our second review of a 10th generation Core i7 part. Earlier this week we put the Core i7-10700 (non-K) through its paces and were surprised by how much performance we could gain by unlocking the power limit.

The "Comet Lake" microarchitecture the Core i7-10700K is based on is hopefully the final implementation of the "Skylake" core design we've been seeing since 2016, using the same 14 nanometer production process. Before AMD "Zen" definitively restored competition in the desktop processor segment, Intel sold no more than four cores in its mainstream desktop segment for the past seven generations. Since then the company has been forced by AMD to increase core/thread counts generation over generation as the company could not increase per-core performance (IPC) because it ran into trouble with its 10 nm silicon fabrication process.



The Intel Core i7-10700K is an 8-core/16-thread part, a doubling in thread count over the 9th Gen Core i7-9700K, which is an 8-core/8-thread part. The L3 cache has also been increased by 33%, up from 12 MB to 16 MB. This is in fact an identical hardware configuration to the Core i9-9900K. Intel gave the chip a slight clock-speed increase; it's now clocked at 3.80 GHz, with a maximum boost frequency of 5.10 GHz, a significant step up from the 2.90 GHz nominal and 4.80 GHz boost clocks of the Core i7-10700.

Our review of the Core i7-10700 revealed that despite being a locked part, a significant amount of performance can be squeezed out of the Core i7-10700 by simply tinkering with the power limits and base clock in your motherboard BIOS. You don't even need the most expensive boards to do this, or liquid cooling setups. The Core i7-10700 was a pleasant surprise and only increased our appetite for the Core i7-10700K, which comes with an unlocked multiplier that makes overclocking a breeze; it also has higher power limits.

In this review, we put the Core i7-10700K through its paces across our test bench to figure out if you could potentially save yourself $100 by choosing it over the Core i9-10900K, or if you're better off spending $100 less and going with the Core i5-10600K. As we mentioned earlier, Intel relaxed several power-management restrictions at the platform level, letting motherboard designers go to town with their VRM solutions and custom power limits. We therefore tested the Core i7-10700K in three configurations. The first (green bar) is the Core i7-10700K straight out of the box, with the motherboard made to respect Intel specs. The second (blue bar) sees us max out the turbo headroom of the processor. The third has us taking advantage of the unlocked multiplier to overclock the chip to a reasonable maximum overclock the majority of users should be able to achieve with air cooling, which is 5.10 GHz all-core, a notch above the Core i9-9900KS limited edition chip.

A Closer Look

Our Core i7-10700K sample came in a tray-only package. The retail packaging includes no heatsink, which means you'll have to spend more money on buying a cooling solution.


The Core i7-10700K looks like any LGA1xxx processor released by Intel in the past decade. The processor is only compatible with socket LGA1200 motherboards because the position of the round notches has been changed. It will not work with an older motherboard.


Luckily, socket LGA1200 retains cooler compatibility with all older LGA115x-series sockets. This means you're going to be spoiled for choice when picking a cooler to go with this processor.

Architecture

Under the hood of the Core i7-10700K is the 10-core "Comet Lake-S" silicon built on the same 14 nm++ process as the previous two generations, with two disabled cores and L3 cache reduced to 16 MB. The die area is estimated to be 200 mm².


The "Comet Lake-S" silicon is laid out similar to the past four generations of Intel mainstream processors, with two rows of CPU cores flanked by the iGPU on one side and the system agent (integrated northbridge) on the other, and a Ringbus Interconnect serving as town square between the various components. The last-level cache is scattered across as slices, adding up to 16 MB of unified L3 cache all cores can access equally.

Much of the processor's uncore components are clumped into the system agent, which contains the memory controller, PCI-Express gen 3.0 root-complex, DMI interface, and memory PHY. The iGPU solution, though present on the silicon, is permanently disabled by Intel. On the other end of the ringbus is the Gen 9.5 integrated graphics, which has practically been carried over for the past three generations, featuring 24 execution units in the GT2 trim. All SKUs in the desktop 10th generation processor series appear to have the top GT2 trim. Don't expect to play PUBG at 4K on this; the "UHD" moniker only indicates that the IGP can handle 4K Ultra HD displays, features modern connectivity options, such as DP 1.4 and HDMI 2.0, and can playback 4K video in new formats with 10-bpc color and HDR10/Dolby Vision standards.


The core itself is identical in design to "Skylake," and there are hence no IPC increases to be had. As we explained in the introduction, all of Intel's efforts to increase gaming, single-threaded, and less-parallelized application performance revolve around increasing clock speeds and deploying as many as three intelligent boosting algorithms to achieve the advertised clock speeds.

The Core i7-10700K has a nameplate base frequency (aka nominal clock) of 3.80 GHz and a maximum Turbo Boost frequency of 5.10 GHz. Unlike the top Core i9-10900K part, it lacks Thermal Velocity Boost and makes do with classic Turbo Boost 2.0 and Turbo Boost Max 3.0. The TDP of the chip is rated at 125 W, compared to the 65 W of the Core i7-10700.

Intel introduced a handful of overclocking enhancements with the 10th generation, including the ability to toggle HyperThreading on a per-core basis rather than globally. This could be an interesting option for those gaming and streaming, where a certain number of cores have HTT disabled for the best gaming performance and certain cores have it enabled, with Windows process core affinity settings taking care of the rest.

The company also introduced the ability to overclock the DMI chipset bus. DMI is a PCIe-based interconnect that handles transfers between the processor and the chipset (PCH). The LGA1200 platform uses DMI 3.0 (comparable to PCI-Express 3.0 x4 in terms of bandwidth). Intel has apparently decoupled PCIe clock domains to enable you to overclock the DMI and PEG (that topmost x16 PCIe slot) without destabilizing your PCIe setup for graphics cards. The unlocked base-clock multiplier makes overclocking the Core i7-10700K a breeze.

The Z490, H470, and B460 Platforms

Z490 is the top 400-series chipset targeted at gaming desktops and PC enthusiasts, as it enables serious overclocking and multi-GPU support. In terms of I/O capabilities, the chipset is nearly identical to the Z390, with 24 downstream PCIe gen 3.0 lanes, six SATA ports, six USB 3.2 gen 2 ports that can be converted to three USB 3.2 gen 2x2 ports, ten USB 3.2 gen 1 ports, and fourteen USB 2.0 ports. Intel is recommending its i225-V 2.5 Gbps Ethernet chip as the wired networking solution to go with Z490, and the company's AX201 802.11ax WiFi 6 WLAN solution to go with the chipset's CNVio interface.


You are more likely to pair locked and entry-level processors such as the Core i3-10100 with the B460 or H470 chipsets. B460 has motherboards start at around the $90 mark. It comes with 16 downstream PCIe gen 3.0 lanes (compared to just 12 on the previous-generation B360). Compared to Z490, you get fewer PCIe lanes (16 vs. 24) from the chipset, and fewer USB 3.2 ports (eight 5 Gbps ports and no 10 Gbps ports compared to six 10 Gbps and ten 5 Gbps ports on the Z490). You also lose out on CPU overclocking features and multi-GPU capabilities (such as SLI). B460 motherboards also come with memory frequency restrictions set to DDR4-2933. The H470 is an interesting middle ground between the Z490 and B460. You still lose out on multi-GPU and overclocking, but get more platform PCIe lanes (20 vs. 16 on the B460 and 24 on the Z490), as well as four 10 Gbps USB 3.2 ports in addition to what you get from the B460.

To take full advantage of the unlocked multiplier and increased power limits of the Core i7-10700K, we recommend you use a Z490 chipset motherboard.

Test Setup

• All applications, games, and processors are tested with the drivers and hardware listed below—no performance results were recycled between test systems.
• All games and applications are tested using the same version.
• All games are set to their highest quality setting unless indicated otherwise.