Introduction

The Core i5-13600K leads the performance-segment of the company's swanky new 13th Gen Core "Raptor Lake" desktop processor family. This $300-ish market segment attracts a wide range of users, from gamers to creators on a budget. You get almost the entire feature-set of the series, at a lower core-count. It joins the Core i9-13900K, which we've also reviewed for you today; besides the i7-13700K. While the Core i5 desktop processor series have historically spanned mid-range prices, Intel has done several value-additions to Core i5 over the years, such that it created two sub-series—the Core i5 K/KF-series, and the non-K/KF; with the two having distinct CPU core-configurations, L3 cache sizes, and other features.



The 13th Gen Core "Raptor Lake" series brings with it generational CPU core-count increases, and the same holds true even for the Core i5-13600K. The chip gets six performance cores (or P-cores), and eight efficient cores (E-cores). This 6P+8E configuration is higher than the 6P+4E one of the previous-generation i5-12600K "Alder Lake," and while it might seem insignificant, given that only the E-core count has increased; Intel also replaced the P-cores with the new "Raptor Cove" ones that come with higher IPC, larger caches, and faster clock speeds.

The 13th Gen Core "Raptor Lake" is Intel's second rodeo with the Hybrid architecture, the 12th Gen Core helped it shore up CPU core-counts and chase down AMD's lead in that area, and Intel is smart about it: the silicon only has six or eight P-cores, which Intel wagers are sufficient for taking on compute-intensive less parallelized tasks; while a swarm of physically smaller E-cores handles most light to moderate workloads, and in a crunch situation (all cores loaded); can contribute greatly to the processor's overall multi-threaded performance. So AMD's advantage with gaming performance is overcome with the high clock-speed P-cores, and its advantage with multi-threaded creator workloads is dusted by E-cores working in concert with the P-cores.

With "Raptor Lake," Intel is introducing new "Raptor Cove" P-cores that come with higher IPC (single-threaded performance at a given clock speed); the ability to sustain higher clock-speeds generationally; and higher amounts of dedicated L2 cache—increased to 2 MB compared to 1.25 MB on the "Golden Cove" cores of "Alder Lake." While the E-cores are the same "Gracemont" ones, the E-core counts have increased generationally, as did their clock speeds and L2 cache sizes. Each "Gracemont" 4-core cluster now shares 4 MB of L2 caches among the cores, compared to 2 MB on "Alder Lake." The Core i5-13600K has two such clusters, and hence eight E-cores. The shared L3 cache size has increased, too, which is now 24 MB compared to 20 MB on the i5-12600K.

The 13th Gen Core "Raptor Lake" processors are built on the same Socket LGA1700 package as the 12th Gen, and are compatible with existing Intel 600-series chipset motherboards via BIOS updates; although they are accompanied by the 700-series chipset motherboards with improved power architecture and downstream PCIe connectivity. The new processors support the same I/O as the 12th Gen, with PCI-Express 5.0 x16 PEG, one PCI-Express 4.0 x4 NVMe slot wired to the processor, and DMI 4.0 x8 chipset-bus. The processors support both DDR4 and DDR5 memory types, improving choice for the consumers.

Intel is pricing the Core i5-13600K at USD $320, a similar price to that of the i5-12600K, and $20 higher than the competing Ryzen 5 7600X. It features a 6P+8E core configuration, and the P-cores tick at 3.50 GHz with a maximum boost frequency of 5.10 GHz, while the E-cores do 2.60 GHz, with up to 3.90 GHz boost. The processor base power (PBP) value is the same as the other processor models launching today, at 125 W, while the maximum turbo power is generationally increased, it's now 181 W. In this review, the i5-13600K squares off against the bulk of the $250-$400 desktop processor segment that's cluttered with chips such as the i5-12600K, 7600X, 7700X, and even i7-12700KF. If you can live without integrated graphics, you can opt for the i5-13600KF over the i5-13600K, which is practically identical, but $25 cheaper, at $295.

Architecture

The "Raptor Lake" microarchitecture is the swansong of monolithic silicon client processors for Intel. Future generations will implement the IDM 2.0 product design, and will be multi-chip modules with chiplets built across various foundry nodes. The "Raptor Lake" silicon is fabricated on the same Intel 7 (10 nm Enhanced SuperFin) foundry node as the previous-gen "Alder Lake," although Intel claims to have squeezed out a handful ofprovements, such as better electron channel mobility, which can let both the P-cores and E-cores gain increases in clock speeds by as much as 600 MHz over the previous-generation, and minimally higher power. The transistor-density is unchanged, since it's the same the node. The "Raptor Lake" die measures 23.8 mm x 11.8 mm (257 mm² die-area).


The channel mobility improvements on the Intel 7 node in particular lets the chip designers raise the V/F curve, with over 50 mV reduction in iso-frequency (voltage needed for frequency); over 200 MHz iso-voltage (frequency increase at a given voltage); which enables up to 600 MHz increase in Turbo Boost frequencies, with the increase of maximum turbo power (MTP) to as high as 253 W for the Core i9-13900K and i7-13700K; and as high as 181 W for the Core i5-13600K.

The "Raptor Cove" performance cores (P-cores) come with increased IPC, and while the company didn't specify the IPC gain over the previous-generation "Golden Cove" P-core, it mentions an over 15% single-threaded performance uplift. The ISA of the "Raptor Cove" core is identical to that of "Golden Cove," but the company has enhanced the hardware prefetcher dealing with the dedicated L2 cache. Helping the P-core performance uplift are the node improvements that help it sustain higher frequencies, and larger dedicated L2 cache—now 2 MB compared to 1.25 MB for "Golden Cove." The i9-13900K and i7-13700K get eight "Raptor Cove" P-cores, which come with HyperThreading enabled, so 16 threads from the P-cores. The Core i5-13600K gets six of these P-cores, for 12 threads.


The "Gracemont" E-cores are architecturally unchanged from "Alder Lake," but are tuned with higher frequencies, and the most important hardware-level change is the L2 cache. Groups of four E-cores are organized as E-core clusters, which share an L2 cache among the cores. Intel doubled this cache size from 2 MB on "Alder Lake" to 4 MB. Much like the P-cores, Intel has updated the L2 cache prefetcher algorithm for E-core clusters. The "Raptor Lake" silicon physically features four E-core clusters, so 16 E-cores in total. The Core i7-13700K is carved out by disabling two of these clusters, giving you eight E-cores; while the i5-13600K is designed by disabling two E-core clusters, as well as two P-cores, for its 6P+8E configuration.


Intel made several other updates to the cache and memory sub-system besides the enlarged L2 caches mentioned above. The shared L3 cache is now as large as 36 MB for the Core i9 SKUs, 30 MB for the Core i7 SKUs, and 24 MB for the Core i5 K/KF SKUs. The Ring Bus interconnect continues to be the town-square for this silicon, and Intel has increased its frequency by 900 MHz, now up to 5.00 GHz (it ran up to 4.10 GHz on the i9-12900K). The new Dynamic INI (inclusive/non-inclusive) architecture lets components reserve portions of the L3 cache to themselves to minimize cache misses or DRAM roundtrips if the cache is saturated. The processor supports dual-channel DDR5 and DDR4 memory types (2x 64-bit channels in case of DDR4, 4x 32-bit sub-channels in case of DDR5). The chip now supports DDR5-5600 natively (JEDEC spec), while the native DDR4 frequency is unchanged at DDR4-3200.


While it didn't put out detailed architectural block-diagrams of its CPU cores like it did the last time, Intel was kind enough to give us a breakdown of how it achieved its claimed 15% single-threaded performance uplift, and >40% multi-threaded uplift. Generational increases to frequency, cache size and prefetcher improvements, and and memory frequency uplifts, add to these. Multi-threaded performance uplift rides on the back of all these; plus the doubling in E-core count. Contributing to not just multi-threaded performance, but also consistency in multi-threaded performance across applications, are a series of updates to Intel Thread Director, the hardware-level middleware that makes Intel's Hybrid architecture work with software, by directing the right kind of workload to the right kind of CPU cores. It collaborates with OS scheduler improvements of Windows 11 22H2, particularly with smarter QoS (performance outlay) for background tasks.


All processor models being launched today are Unlocked K (or KF) SKUs, letting you go to town with overclocking. While there are no new overclocking handles with "Raptor Lake," Intel improved the software side of things, by giving Extreme Tuner Utility (XTU) new per-core multiplier settings for both the P-cores and E-cores; and a simplified UI for automated overclocking, with Speed Optimizer.

Intel Z790 Chipset

Alongside the six 13th Gen K-series processors SKUs, Intel is debuting the Z790 chipset. Motherboards based on this are guaranteed to come with out-of-the-box support for 13th Gen processors, even though 600-series chipset motherboards support them via a BIOS update, and many of them feature USB BIOS Flashback. The Z790 sees a rebalancing of the downstream PCIe connectivity in favor of more downstream Gen 4 PCIe lanes, compared to the previous-gen Z690. You will find Z790 motherboards with DDR5 memory support, as well as those with DDR4 support—Intel hasn't restricted motherboard vendors from doing so.

Unboxing and Photography

As we detailed in our Unboxing Article, our Core i9-13900K and i5-13600K samples came in special media-kits. It's basically a flashy paperboard box the size of an M-ATX motherboard box, with the two processors inside, and some mementos designed to look like the "Raptor Lake" die.


The memento should go well as a backdrop item for video-format tech journalists. The retail Core i5-13600K comes in a simple paperboard box, which lacks a boxed cooler.


The Core i5-13600K processor package looks like the 12th Gen processors, as it shares the same LGA1700 socket. It's backwards-compatible with 600-series chipset motherboards with BIOS update. Many of the premium models come with USB Flashback.


The retail Core i5-13600K box doesn't include a cooler, but you can pick up just any LGA1700 cooler—there's plenty of choice. Just make sure it can handle the thermal load.

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.

AIDA64 Cache and Memory Performance

In this first test we're looking at the performance offered by the memory subsystem and the processor's L1, L2 and L3 caches. AIDA64 comes with a great benchmark that provides a nice overview over all these performance characteristics.

Super Pi

SuperPi is one of the most popular benchmarks with overclockers and tweakers. It has been used in world-record competitions practically forever. It is a purely single-threaded CPU test that calculates Pi to a large number of digits—32 million for our testing. Released in 1995, it only supports x86 floating-point instructions and thus makes for a good test for single-threaded legacy application performance.