12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

For the second time in a year, Intel has dropped a new generation of CPUs for our PCs. The 12th generation Intel CPUs, codenamed Alder Lake, promise to be more powerful and more efficient than their predecessors. This is down to a totally new design that moves away from that of the past few years. This change presents users with advantages and disadvantages.

Over the past few years, Intel had been effectively been presenting the same series of CPUs each year with the odd tweak and new feature thrown in. They have been so similar that we’ve even been able to get away with using the same motherboard across generations, albeit with some restrictions.

For the 12th generation of Intel’s CPUs, it’s all changed. Intel sent over a Core i5-12600K and a Core i9-12900K for us to test.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

To accommodate these new chips, PCs will need a new motherboard, and perhaps a new cooler. Users wanting to make the most of their new CPUs will also need to source some ridiculously expensive DDR5 memory, an upgrade from the current DDR4 memory that’s rather scarce at the moment but, for the moment, at least, not really that much faster.

There are 12th generation motherboards that can still use DDR4 memory and, in the absence of being able to economically procure any DDR5 modules that’s what we used to test these new CPUs.

The test machine consisted of an ASUS TUF Gaming Z690-Plus WiFi D4 motherboard with CPU cooling via a Corsair H150i Elite LCD all-in-one cooler, 16GB of Kingston Fury Renegade DDR4-4600 RAM, and Nvidia RTX 2080 Ti GPU, all encompassed in a very airy Corsair 7000D Airflow tower case.

Being “K” CPUs, both the Core i5-12600K and Core i9-12900K CPUs are unlocked and thus capable of being overclocked. For the tests, I used the AI overclock built into the Asus motherboard to give the CPUs a boost. This is not an extreme overclock by manually adjusting voltages and clock timings, just the board tweaking the CPU according to performance. I’d expect anyone buying unlocked CPUs like these to at least take advantage of this sort of facility. With Asus boards, it’s an easy one-click solution that ensures that you get the most out of your investment, as long as you have a decent cooling solution.

Anticipating some raised temperatures with the i9 and wanting to simulate a reasonable build for housing a $1000 CPU, I figured a decent AIO cooler was in order. The Corsair H150i Elite LCD cooler has a 360mm radiator equipped with three 120mm fans pushing an airflow between 14.86 – 58.10 CFM. This fan is one of the first to come complete with standoffs suitable for the Alder Lake CPUs’ LGA 1700 sockets. My cooler arrived without the LGA 1700 parts which could have been a problem. Thankfully, the H150i Elite LCD is essentially the same spec as an iCue H150i Elite Capellix CPU cooler, for which Corsair sells LGA 1700 update kits.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The H150i Elite LCD radiator is over 400mm long, necessitating a case that could accommodate it. With GPUs getting bigger and bigger, replacing the previous test rig case with a tower seemed like a good idea. Enter the Corsair 7000D Airflow tower case. With its three sock fans, the 7000D Airflow pushes a fair amount of air across your components. The case has room for over a dozen fans should I wish to increase the flow to the max in the future. Even the huge ASUS TUF Gaming Z690-Plus WiFi D4 motherboard looks tiny in the huge internal cavity of the 7000D, perfect for a test rig that’s constantly having components swapped out.

For the actual testing, in addition to my old favourites, the readily available Performance Test 10.1, Cinebench R.23, and the Blender 2.931 benchmark, I drafted in a few more tests. The idea is to not only check performance from a theoretical stance but to use tools capable of simulating real-world applications.

3D Mark is a test app that I usually reserve for GPUs, but the recent addition of the CPU Profile test makes it a good tool for checking CPUs as well. As well as the new CPU Profile tests, I also ran the Timespy Extreme benchmark to obtain comparable CPU scores in a more game-like setting.

3D Mark’s stablemate, PC Mark 10, is a fairly inexpensive suite of benchmark tests that use real-world application scenarios. The test can be used to derive PC performance in a range of tasks including office productivity, video editing, and photo editing. The suite uses freeware programs running scripts to gauge the benchmark results.

Procyon is PC Mark’s big brother, the professional benchmarking suite from UL. The office productivity test uses an installation of Microsoft Office to obtain real-world scores using Word, Excel, etc. The photo editing benchmark using Adobe Lightroom to, again, obtain real performance benchmarks. The video editing benchmark runs Adobe Premiere Pro to evaluate performance. Using commercial software packages UL Procyon provides a valuable insight into system performance in a non-simulated, real-world environment.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

CrossMark from BapCo is a cross-architecture performance benchmark program aimed at professional users. It’s an unbiased test that can be used to compare performance across multiple platforms such as Windows, iOS, macOS, iPadOS, and Android. The one test uses open-source applications to assess systems and provide scores across productivity, creativity, and responsiveness.

Performance Test 10.1 is an inexpensive benchmark that is used to score the entire system. It is available as a time-limited evaluation and good for a quick check that everything is working OK. The program not only scores each individual component (CPU, RAM, storage, etc.) but also yields a percentile comparison with other systems that have performed the tests.

Cinebench R.23 is a good freeware test as it checks not only multi-core speeds but also single-core speeds. With most marketing touting a CPU’s top speed, which is usually on a single or with only a couple of cores in use, this figure can be misleading when using software that’s making full use of the CPU. Based on the Cinebench 3D modelling and rendering suite Cinebench offers another real-world test.

Finally, the Blender 2.931 benchmark. This uses the latest version of the open-source rendering software to provide benchmark rendering times across several projects for a direct comparison of system performance with the Blender rendering engine.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

Installation of the CPUs should be no trouble for anyone that has installed Intel chips in the past. The LGA 1700 socket is slightly longer than previous iterations, but providing you spot and match up the little triangles on the socket and the CPU, you can’t go wrong. For the i5-12600K tests, I used the thermal paste reapplied to the AIO cooler, but for the i9-12900K I used a blob of Arctic MX-4 thermal paste.

As a sensibility check, I carried out the same benchmark tests using the Core i9-10900K review rig, sporting an Nvidia RTX 3090. As we are only interested in the PCU results, the superior performance of the RTX GPU isn’t an issue, as the results will reveal.

Prior to the installation of the 12th-Gen CPUs, the test rig was running a Core i9-11900K. Whilst an impressive CPU, it was not much of an upgrade from its 10th-Gen counterpart. I found the 11th-Gen Core i9 to run hot with thermal and power throttling getting in the way of its potential. The less-than-impressive performance of the 11th-Gen CPU is likely due to Intel wringing the last bit of power out of the 14nm process that they have been employing since 2014.

For the 12th-Gen CPUs Intel has switched to a 10mn process which they refer to as Intel 7. This, with the inclusion of two types of processor cores, should see some interesting gains. The performance cores (P-cores) are the main CPU cores designed for single and lightly threaded performance tasks like those associated with gaming and productivity application. The Efficient-cores (E-cores) are optimised for scaling multi-threaded workloads and minimise interruptions from background tasks. Threads and workloads are handled by the built-in thread director which works with the operating system to allocate tasks.

On the subject of operating systems, Windows 11 is recommended to get the most out of 12th-Gen CPUs, and you may see some performance gains. Most people running Windows 10 should have had the opportunity to upgrade to Windows 11 free of charge by now.

On to the results.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

First up was the Core i5-12600K. I loved the bang for your buck that the i5-11600K gave me, so I was expecting big things from this CPU. What I didn’t expect was for it to leave my Core i9-10900K in its dust. For a mid-range CPU, costing half the price of the top-of-the-range CPU from only just over a year ago, to beat it is a shocker.

The Core i5-12600K is an unlocked CPU with 10 cores. That six performance cores and four efficient cores. The stock P-core maximum turbo frequency is 4.90 GHz with the E-core maximum at 3.60 GHz. The Asus motherboard AI overclock took the P-core maximum for two active cores to 5.0 GHz, three to four active cores to 4.8 GHz, and five to six to 4.6 GHz. The one-click overclock raised the E-core frequency to 3.7 GHz across the board.

It also has integrated Intel UHD Graphics 770 which is fine for casual use but nothing else. I expect a non-GPU equipped CPU to be released soon, but for the minuscule cost-saving, it’s probably worth having the UHD GPU to fall back on or to run a supplementary display.

Across the PC Mark, UL Procyon, Crossmark, Performance Test, and Cinebench result, the Core i5-12600K beat the Core i9-10900K. It was only with the Blender result, which was pretty much in parity, and the 3D Mark CPU score that the new i5 didn’t hold its ground so much. The 3D Mark CPU thread tests were about equal, the gap widening with fewer threads under test. The division of work between the P and E core may be something to do with this, but still an excellent result.

Checking Core i5-12600K temperatures using the Intel Extreme Tuning Utility stress test have the CPU reaching a max temp of 60-degrees with an average of around 50-degrees C. This is with all 10 cores running flat out at 100%. The utility also did not report any power or thermal throttling during the 20-minute stress test.

Whist the detailed results can be viewed below, as an overview, it would be fair to say that a 12th-Gen Intel Core i5-12600K performs at a similar level to that of a 2020 10th-Gen Intel Core i9-10900K CPU. These results make the Core i5-12600K a very good CPU for gaming and application performance. It also seems to be a very cool CPU, topping out at 50-degrees, making me wonder how much headroom it has for the dedicated overclocker.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The Core i9-12900K is the flagship of Intel’s 12th-generation family of CPUs. packed with a whopping 16 cores and, like the i5 manufactured using 10nm fabrication, this could be the ultimate gaming CPU. The CPU has 16 cores, that’s 8 performance cores and 8 efficient cores. The base P-core max boost is 5.1 GHz with the E-cores’ being 3.9GHz. The ASUS AI overclock increased this to 5.3GHz for a single P-core, 5.2GHz for 2 cores, 5.1 for 3-4 cores, and 5.0 for 5-8 cores. For the E-cores the basic AI overclock boosted the frequencies to 4.0GHz. As with the Core i5, the i9 has integrated Intel UHD Graphics 770.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The i9 was tested using the same ASUS motherboard, memory, and cooling solution. I went in expecting big things but wasn’t quite expecting these results. In every test, the 12th-Gen CPU performed significantly better than both my existing 10th-Gen i9-10900K and the 12th-Gen i5-12600K.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

For the Core i9-12900K, the PC Mark 10 tests yielded an average performance increase of 29% over the 10th-Gen i9 and 12% over the Core i5-12600K. Of note was the whopping 54% increase for the main PC Mark 10 score over the Core i9-10900K.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

UL Procyon averaged a 34.13% increase over the 10th-Gen Core i9 and 8.6% over the 12th-Gen Core i5. Crossmark produced similar results with a 45.22% increase over the Core i9-10800K and 14.1% over the Core i5-12600K.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The Core i9-12900K bumped the Performance Test 10.1 percentile result up to perform better than 96% of tested machines. For the Cinebench tests, the single-core result was 1821 compared to the i5’s 1784, but still significantly better than the i9-10800K’s 1269. The Cinebench multicore test raced ahead up to 25343 from the i5’s 17113 and the 10th-Gen i9’s 14291.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The Blender rendering test saw the Core i9-12900K render over a minute faster than that of the Core i5-12600K across all the scenes. The 3D Mark CPU profile results showed the Core i9-12900K performing over 30% better than the i5 and the 10th-Gen i9, but only marginally faster than the i5 for single the thread score. The 3D Mark TimeSpy Extreme CPU score again saw the i9 scoring over 30% better than the other CPUs.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The Intel Extreme stress test with the Core i9-12900K running at 100% across 16 cores saw the CPU reach a maximum temperature of 81-degrees C, averaging at 71-degrees. As with the i5, there was no thermal or power throttling during the test.

12th Generation Intel Core i5-12600K and Core i9-12900K CPU review

The results for the Core i9-12900K show a CPU that offers a significant upgrade over a two-year-old Intel i9 PC. Users putting the CPU to work on productivity applications will get the best out of the CPU, as will gamers playing games initialising multiple cores. Older titles will likely not see much of a performance boost.

As well as performance, there are other reasons why an upgrade to Intel’s 12th-Gen CPUs may be in order. As I’ve mentioned, DDR5 is not really a good enough reason right now, but it will be as the modules get faster and (hopefully) cheaper. PCI 5.0 is another new technology that is perhaps a little before its time with the 12th-Gen CPUs, but with compatible SSD promising 13,000MB/s transfer speed just around the corner, it’s worth watching.

After the less-than-dramatic performance increases I saw from the 10th-Gen to the 11th-Gen, I wasn’t expecting much from the Alder Lake CPUs. It would seem that the 10nm production technology has yielded CPUs that can not only operate faster but also at lower temperatures.

As is always the case, it’s the Core i5 that offers gamers the best bang for their buck, with the i9’s price tag making it only for the most discerning gamer. Users wanting top-of-class performance will, however, be very happy with the performance gains to had from the Core i9-12900K.