Mission accomplished! Intel has achieved what many have doubted. Their new Alder Lake architecture is a huge improvement over previous generations. Intel not only said bye-bye to "Skylake" with 12th Gen, they also introduced a number of technological improvements, like big.LITTLE cores, DDR5 memory, and PCI-Express 5.0. With these changes came the requirement for a new socket yet again, but this time around, there's an actual reason for the change that goes beyond "hey let's change up things so we and our motherboard vendor friends can sell more stuff." Earlier today we posted a huge comparison article that goes into details on all the announced Z690 motherboards.

Besides this processor review, we have more content for you today: Core i9-12900K, Core i7-12700K, Core i5-12600K, ASUS ROG Maximum Z690 Hero, and Intel Z690 Motherboard Comparison

In terms of overall performance, the Core i9-12900K can impress. Thanks to the unbelievable single-threaded performance of the Golden Cove P-cores, the CPU rushes ahead in everything that's single-threaded or low-threaded. For situations where full power is not needed, Intel has added efficient "E-cores," which are slower, but help keep overall power usage down. Armed with eight P-cores and eight E-cores for a total of 24 threads, the Core i9-12900K beats the 12c/24t Ryzen 9 5900X in nearly all our tests. On average, the new Intel flagship is 5% faster. Compared to the much more expensive 16-core/32-thread Ryzen 9 5950X, the Core i9-12900K performs admirably and even beats it in some scenarios that typically scale mostly with core counts, like rendering, so color me impressed.

Not everything ran perfectly, though. In several of our tests, the workload got scheduled onto the wrong cores. We did use Windows 11 for all our testing, which has proper support for the big.LITTLE architecture of Alder Lake and includes the AMD L3 cache fix, too. Intel allocated extra silicon estate for "Thread Director," an AI-powered network in the CPU that's optimized to tell the OS where to place threads. However, several of our tests still showed very low performance. While wPrime as an old synthetic benchmark might not be a big deal, I'm puzzled by the highly popular MySQL database server not getting placed into the P-cores. Maybe the logic is "but it's a server background process"? In that case, that logic is flawed. If a process is bottlenecked by around half (!) and it's the only process on the machine using a vast majority of processor resources, doesn't it deserve to go onto the high-performance cores instead? I would say so. Higher performance would not only achieve higher throughput, and faster answers to user requests, but it would also reduce power consumption because queries would be completed much faster. Other reviewers I've talked to have seen similar (few) placement issues with other software, so it seems Intel and Microsoft still have work to do. On the other hand, for gaming, Thread Director works pretty much perfectly. We didn't have time to test Alder Lake on Windows 10 yet—that article is coming next week.

Intel announced the Core i9-12900K as the "world's best CPU for gaming," and after the fail of 11th Gen Rocket Lake where similar claims ended up being completely untrue, I wasn't expecting much. Oh boy, was I wrong. The 12900K is really the world's fastest gaming processor, and it claims that title with quite a significant margin. At the academically interesting fully CPU-limited resolution of 720p, we see an almost 10% lead over the Zen 3 Ryzens and 15% over Comet Lake and Rocket Lake. Very impressive. As we move up through the resolutions, the differences become smaller, as expected, because the GPU becomes more and more of a limiting factor in how many FPS can be achieved. Still, the Core i9-12900K and other Alder Lake CPUs we tested today stay ahead fairly consistently. At the GPU-limited resolution of 4K, we still see a 2% performance lead over older processors from both AMD and Intel—a surprisingly big difference. I expected less. To put things into perspective, gaining 2% at a graphics card price of $1000 equates to $20, so it's still not enough to make a huge difference in terms of value.

Alder Lake is the first desktop processor fabricated on Intel's 10 nanometer production process, which the company renamed "Intel 7" to reach parity with TSMC's 7 nanometer node used for the AMD Zen 3 Ryzens. While a lot can and has been argued about the naming, what I think matters more is the energy-efficiency of the final product. Here, the Core i9-12900K cannot impress. While our power consumption testing shows that efficiency is significantly improved over previous 14 nm products like Rocket Lake and Comet Lake, it's still nowhere close to what AMD's Ryzen processors offer. To make things worse, Intel chose to essentially abandon any power limits on the Core i9-12900K, a processor "rated" for 125 W. In reality, the power limit is set to 241 W, which pretty much lets the processor suck as much power as it wants and negatively affects energy efficiency at the cost of higher performance. With close to 300 W during our multi-threaded power consumption benchmark, the 12900K uses A LOT more power than Zen 3 (5900X=183 W, 5950X=179 W). On the other hand, the delivered performance is higher, but not to where it makes up for this difference in power consumption.

All this energy has to go somewhere, and that's the job of the CPU cooler. We've been using a Noctua NH-U12S for all our CPU reviews, and it almost feels like it's too weak for the Core i9-12900K at stock (!!). When fully loaded, temperatures quickly climb into the 90°C range and above. Given a heat output of 240 W, this isn't surprising at all. AMD's Ryzens, on the other hand, run at much lower temperatures using the same cooler. We also did some testing with an Arctic Liquid Freezer II 360 mm, which could handle the heat output with ease and achieved much better temperatures.

While I didn't have much time for overclocking the Core i9-12900K, the results so far are disappointing. My highest stable all-core overclock is 4.9 or 5.0 GHz. The biggest issue here is that insane voltage is required for all-core stability at this setting, like 1.5 V. This of course makes the processor pump out even more heat; as such, there is no way to do this without watercooling. Even when watercooled by our 360 mm AIO from Arctic, the temperature reached close to 100°C when fully loaded. Out of the box, the Core i9-12900K will boost up to 5.2 GHz, which means even an all-core OC of 5.0 GHz will be slower in lightly.threaded workloads than what you get out of the box at stock. This essentially means overclocking is not worth it on the 12900K because the CPU is already configured to maximize its potential by default. In previous reviews, we saw good gains from disabling the various power limiters on the Intel CPU, which can be done even with a non-K model. I did a full test run with that, and the gains are only minimal, mostly because the 241 W default limit is enough for all workloads the CPU will encounter. The takeaway here is that buying an unlocked K processor seems to be a waste of money on Alder Lake. Rather, go for the more affordable non-K or even -KF SKUs when they are released next year.

Unlike my 11th Gen Rocket Lake experience, where I felt the platform was full of bugs and rushed, I had zero issues with Alder Lake. The BIOS of my ASUS motherboard feels stable and feature complete, DDR5 memory just worked, click XMP, done. I also didn't encounter any crashes or unexpected issues while testing in Windows 11, like for many my biggest issue is still with the Start Menu and other UI annoyances.

Priced at $600, the Core i9-12900K is not cheap, having gone up in price once again compared to the Core i9-11900K. However, unlike Rocket Lake, Alder Lake is truly a beast of a CPU that introduces big performance gains that can be worth it for many scenarios. The new release will certainly put pressure on AMD, who have been enjoying market dominance for quite some time, so they could overprice their offerings. Compared to the Ryzen 9 5900X, the 12900K offers similar price/performance, but with slightly higher overall performance in applications and gaming. Please do look at our individual test results, there are many tests where the differences are quite big, especially when lightly threaded. I also feel the Ryzen 9 5950X will have to come down in price, too, because it doesn't offer that much over the 12900K. By far the strongest competition for the 12900K comes from Intel's own lineup. We tested all three new processor releases today.and found that the $420 Core i7-12700K offers performance very similar to the 12900K, which isn't surprising because both processors have the same eight performance cores, only the number of E-cores is different at 4 vs. 8—hardly worth a $200 price difference. If you're a gamer at 1440p or 4K, you should seriously consider saving money on the processor to free up budget for the graphics card as that has the biggest effect on FPS rates per dollar spent. Overall platform cost is an issue for Intel's 12th Gen Alder Lake as motherboard prices have gone up significantly for no apparent reason, and the new DDR5 memory comes at premium pricing, too.

Just to provide a little bit of extra info on why I gave "Recommended" to the 12900K, but "Editor's Choice" to the 12700K and 12600K. I feel like the super-high power limit on the 12900K is just pushing things too high, probably for the sake of wining Cinebench, with limited gains in real-world usage, and too much of a toll on power and heat.