Intel i9 12900K and i5 12600K Review: The Next Generation

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Intel unveils the 12th Gen Intel Core processor family (Credit: Intel Corporation)
Intel unveils the 12th Gen Intel Core processor family (Credit: Intel Corporation)

Without further delay, we can finally introduce Intel’s newest process node, Intel 7, for mainstream consumers. Intel has had a rocky road transitioning from their 14 nm process and is introducing a CPU with significant changes. The Intel i9-12900K and i5-12600K processors we have here today are part of Intel’s Alder Lake CPU line-up and bring with it some radical changes over its predecessors. These changes and improvements are covered in-depth in our specifications and features section below.

The flagship CPU using the new Intel 7 process node, previously referred to as Intel 10nm Enhanced SuperFin, is a 16-core, 24-thread CPU with a maximum boost speed of 5.2 GHz for the P-Cores and 3.9 GHz for the E-Cores; we’ll elaborate on this later. This time around, the i9-12900K costs about $50.00 more than the 11900K with an MSRP of $589.00 (Preorder at Newegg $649). We have included a list of SKUs with specifications and pricing below as well.

Today we are pitting AMD against Intel, and we’ll see who comes out as a winner in our testing suite. The showdown will include the i9-12900K (16-core @ $589) and the i5-12600K (10-core @ $289) from Intel up against the Ryzen 9 5950X (16-core @ $749) and the Ryzen 7 5800X (8-core @ $394) in an effort to align core count and pricing.

Specifications and Features

Intel’s engineering team has taken a bold approach with Alder Lake combining performance cores and efficient cores into one die designed to take advantage of the benefits both have to offer. Looking at the i9 12900K, we have eight performance cores (P-Cores) that incorporate Intel Hyperthreading technology for a total of 16 threads. These cores can boost up to 5.2 GHz optimized for single and lightly threaded performance. In addition to the P-Cores, the i9 12900K utilizes eight efficient cores (E-Cores) in two 4-core clusters, optimized for highly-threaded workloads with a turbo boost of up to 3.9 GHz. The i5 12600K is a scaled-down version offering six P-Cores with 12 threads boosting to 4.9 GHz and four E-Cores, which boost up to 3.6 GHz. Only the P-Cores have hyperthreading capabilities hence the odd thread count of the CPUs.


Intel Alder Lake Improvements
Intel Alder Lake Improvements, Image Courtesy of Intel

Memory Enhancements

Alder Lake introduces a couple of new technologies to the mainstream. On top of the new Intel7 process, we’re also introducing DDR5. The new CPUs can run either DDR4 with officially supported speeds up to 3200 MHz in Gear1 and DDR5 modules up to 4800 MHz in Gear2. The maximum capacity for both is 128 GB in a two DIMM per channel configuration.

With this launch, Intel has updated Intel XMP 3.0 support for DDR5 with expanded capabilities. Intel’s XMP has been around for quite some time, and with it, users were introduced to a one-click memory overclocking profile. These profiles are tested across platforms with Intel’s XMP test to aid with compatibility.

DDR5 also brings with it advancements in memory module voltage control. The new memory standard now incorporates a PMIC (power management IC) into the DIMM. In effect, this moves the VDD, VDDQ, and VPP voltage rails from the motherboard to the memory module.

With Intel XMP 3.0, we now have much more flexibility with up to five XMP profiles stored in the modules. The vendor profiles have increased from two up to three, but the most remarkable part is that we now have access to rewritable, customizable profiles. Profile naming has also improved, allowing up to 16 characters for more descriptive naming. Accessing this programming feature requires memory vendor-specific software support such as iCUE from Corsair.

Intel XMP 3.0 image courtesy of Intel
Intel XMP 3.0, Image Courtesy of Intel

Intel Thread Director

With the Alder Lake series of processors, Intel introduces a hybrid core design with P-Cores and E-Cores, designed for different workloads. Doing so helps maximize performance per Watt, but physical and operating system changes were needed to maximize efficiency. Intel devised the Intel Thread Director and worked closely with Microsoft on Windows 11 to optimize the operating system’s scheduler for Alder Lake CPUs to accommodate thread scheduling.

Intel Thread Director helps to monitor and analyze performance data in real-time to seamlessly place the right application thread on the right core and optimize performance per watt.

Intel Thread Director, Image courtesy of Intel
Intel Thread Director, Image Courtesy of Intel

The OS (Operating System) will send a thread to the P-Cores by default, so one P-Core needs to be active at all times if you choose to disable cores in BIOS. The Intel Thread Director, using an AI-trained model, will then send feedback to the OS. The OS sees the demand and schedules threads to either P-cores or E-cores, depending on the type of load. It prioritizes the throughput, pushing background tasks off onto the E-Cores.

As an example, Gaming and streaming simultaneously. The game itself will run through the performance cores, and the streaming/recording end of things uses the efficient multi-threading cores giving a boost to the in-game FPS (frames per second) compared to the 11900K.

Thread Director Comparison for Gaming Image Courtesy of Intel
Thread Director Comparison for Gaming, Image Courtesy of Intel

Intel Smart Cache

With the new core design in Alder Lake, Intel needed to make some changes to its cache architecture. They allotted 1.25 MB of L2 cache for each P-core and 2.0 MB of L2 cache for each efficient 4-core cluster. Doing the math gives the i9 12900K a total of 14 MB L2 cache and the 12600K a total of 9.5 MB L2 cache between the P-Cores and E-Cores. On top of that, the i9 12900K has 30 MB of L3 Intel Smart Cache. The shared L3 cache size is dependant on the CPU, as we see with the 12700K having 25 MB and the 12600K reduced to 20 MB of L3 cache, a significant increase over previous generations reducing latency by keeping more work close to the CPU cores.

12th Gen Cache Architecture Image courtesy of Intel
12th Gen Cache Architecture, Image Courtesy of Intel

Below is a list of the new Alder Lake unlocked CPUs with specifications and pricing; keep in mind this is MSRP.

Alder Lake CPU Specifications and Pricing Image courtesy of Intel
Alder Lake CPU Specifications and Pricing, Image courtesy of Intel

Z690 and Socket 1700

Now for motherboard support and platform improvements: With Alder Lake CPUs, we also have a new socket, LGA 1700. Meaning, adopting the new platform will require a new LGA 1700 motherboard and compatible cooler as the hole spacing on the motherboards has changed.  Currently, some cooler vendors are offering an upgrade package to accommodate the new socket.  Something to keep in mind if contemplating a system upgrade.

Another first with the Alder Lake launch is PCIe 5.0 (32 GT/s transfer rate) compatibility from the CPU. We end up with a varied mix of PCIe standards between the CPU and the Z690 chipset, including PCIe 4.0 and PCIe 3.0 lanes. We’ll attempt to break this down as clearly as we can.

The new i9 12900K has 20 dedicated PCIe lanes; 16 of these are PCIe 5.0 (32 GT/s) in either an X16 or X8/X8 format. We also have four PCIe 4.0 (16 GT/s) lanes for storage devices. That brings us to the Z690 chipset, and thanks to Intel’s DMI 4.0 x8 link, which has double the transfer capabilities of the DMI 3.0 link, we have an additional 28 PCIe lanes. These lanes are broken down into 12 PCIe 4.0 and 16 PCIe 3.0 enabling massive connectivity on the Alder Lake platform.

Intel Z690 Chipset Layout Image courtesy of Intel
Intel Z690 Chipset Layout, Image Courtesy of Intel

We’ll also see native support for additional USB 3.2 Gen 2×2 (20 Gbps) through the chipset and Thunderbolt 4 (40 Gbps) for USB connectivity using Intel’s Maple Ridge controller. Thunderbolt 4 doesn’t offer any additional data transfer bandwidth but does improve video output now with resolutions up to 8K, dual 4K monitor support, and improved security with Intel VT-d DMA protection. The platform also comes with integrated Intel Wi-Fi 6E (Gig+), Intel Killer 2.5G, and integrated support for Intel I219-V LAN.

Intel 600 Chipset Image Courtesy of Intel
Intel 600 Chipset, Image Courtesy of Intel

Overclocking Enhancements

With Alder Lake CPUs produced on a smaller node, this changes the thermal characteristics of the die. It packs the same amount of heat but in a smaller area. To help alleviate the heat, Intel redesigned their IHS (Integrated Heatsink) package. As you will see in the image below, as the generations progressed, the dies got thinner; Intel reduced the thickness of their STIM (Solder Thermal Interface Material) on the 12th Gen, leaving more room for a thicker IHS. The added mass of the IHS, in theory, should aid in wicking heat away from the die and transferring it to the cooler.

Thermal Improvements Image Courtesy of Intel
Thermal Improvements, Image Courtesy of Intel

CPU overclocking still maintains many of the same tuning knobs. In addition to the typical ratio settings, we now have separate P-Cores and E-Core settings. We can adjust the multipliers on a per-core basis, disable hyperthreading on a per-core basis, and disable/enable specific cores or E-Core clusters as long as one P-Core remains active. Intel has alluded to leaving headroom for overclocking and that we won’t be disappointed. We’ll see how that goes in our Pushing the Limits section.

Intel is also updating its Xtreme Tuning Utility (XTU) for the 12th Gen Alder Lake CPUs, adding additional tuning knobs to accommodate the Hybrid Core structure and DDR5. Intel Dynamic Memory Boost, when enabled in BIOS, will switch between the JEDEC standard and the XMP profiles, almost like a “Turbo mode” for the memory. Ideal for saving as much power as possible when the PC is idle, checking email, or just watching movies. We also see the Intel Speed Optimizer again for an easy one-click overclock that automatically adjusts core ratios and voltages, so you don’t have to.

Intel XTU Ver. 7.5 Image Courtesy of Intel
Intel XTU Ver. 7.5, Image Courtesy of Intel

As always, keep in mind that Intel considers setting XMP to be overclocking.

Turbo Boost and Efficiency

We’re all familiar (or not) with Intel’s collection of turbo boost technologies that accelerate the CPU frequency depending on factors such as power use and temperature. With Alder Lake, they have trimmed down the various names and have left us with two. ABT (Adaptive Boost Technology), first introduced on the 11th Gen Rocket Lake CPUs, is gone, and so is Turbo Boost 2.0. We now have Turbo Boost Max, an all-core boost for the P-Cores and E-Cores, although they run different speeds. Then we have Turbo Boost Max 3.0 for lightly threaded loads, optimizing performance by sending work to your fastest cores. This technology is only used on the P-Cores and is not available on all Alder Lake CPUs.

We still have two different power levels for the operating window of the CPU. PL1 (Power Level 1) is the processor’s base power or default and remains 125 W for continual operation. PL2 is the maximum turbo power which varies by CPU. PL2 is 241 W for the 12900K, 190 W for the 12700K, and 150 W for the 12600K. Keep in mind that many motherboard vendors default to PL1 = PL2, so the processor runs at maximum turbo out of the box.

Performance vs. efficiency is the bar that has guided new tech for generations. This concept is what drove Intel to design a hybrid CPU. Ideally, it should deliver the best of both worlds—outstanding single-threaded performance as well as improved multi-threaded performance. According to Intel’s internal testing, one cluster of four E-Cores occupies the same area on the die as one P-Core but delivers 1.6x the performance in multi-threaded workloads. Comparing the whole 12900K package to the 11900K Rocket Lake, Intel claims a 50% performance gain at 241 W and on par performance at 65W for multi-threaded workloads. In other words, the same performance but using 1/4 the power, if true, is quite impressive.

Hybrid Power Comparison Image Courtesy of Intel
Hybrid Power Comparison, Image Courtesy of Intel


Intel has also incorporated the new Enhanced Intel Xe graphics into the Alder Lake CPUs, namely, the Intel UHD Graphics 770.  The new iGPU has 32 execution units with high-efficiency dual encoders, supports up to a single 8K HDR or four 4K HDR displays simultaneously. It also has support for Display Port 1.4a and HDMI 2.0b connectivity. The specifications are listed as Intel UHD Graphics 770 and are only available in the Alder Lake CPUs. We cannot compare performance with the UHD 750 graphics but will update in the future.

Meet the i9-12900K and i5-12600K

Here’s a slideshow of the sample packaging, which differs from retail, some close-ups of the CPUs’ top and bottom, plus a comparison of the i9-12900K and the i9-11900K.  Overall you can see the shape has changed from a square to a rectangle shape. Pad orientation is entirely different with a significant addition, and the pads themselves are quite a bit smaller. You’ll also notice a change to the IHS in shape and size.

This slideshow requires JavaScript.

Shawn Jennings – Johan45

Unfortunately, due to some miscommunication, we are unable to offer any performance details at this time. When we receive the required hardware, we will update this review with performance data.

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  1. Voodoo Rufus
    This is more of a preview than a review, in all honesty.

    I fully intended on having a review up for release but....
    The last few launches Intel would send CPUs and mobos etc.. all you need to run and test. This time there was no heads up and all we received were the CPUs. Long story short I should have performance data up in a week or so still don't have a motherboard in hand.