Final Words & Conclusion
The Core i5 9600K, arguably is merely a Coffee Lake-S series refresh, in essence, an 8700K lacking hyper-threading. So from a threading performance point of view, it is not surprising to see this processor somewhere in the middle of everything. It certainly is not a mega-threading monster crunching away your video renders.
The reality, however, is that Intel is cashing in on one of their strong point, high clock frequencies. And since games only need up-to six threads (mostly), the biggest benefit is a faster-clocked core. The instructions per core can be calculated faster, and that drives up your gaming framerates if your graphics card isn't GPU limited. As you have been able to see, it is in that respect where the Core 9000 series processors will shine, as the extraordinary high clock frequencies boost overall game performance. I immediately need to make a side-note here, that performance difference you're only going to see with the 1000 USD and more expensive graphics cards as really, these only run into GPU limitation ay Ultra HD. But the reality is simple, the Core 9000 series will be an excellent gaming processors. And that will be the thorn in the eyes of AMD as they cannot pass that ~4.2 GHz marker. AMD's answer for that needs to be ZEN2. So yes, Intel's new Core i5 9600K manages to impress with gaming. Strictly speaking though as you have seen, if you look at IPC at 3500 MHz then Coffee Lake certainly isn't faster compared to the previous gen product, in fact, they are merely a few points away from Ryzen in that respect. So yes, Intel benefits greatly from the fact that they can reach high clock frequencies. That base clock of 3.7 GHz is a little confusing to me, as the six cores never drop below 4.3 GHz. In a default non-overclocked setup, the platform also manages heat and power consumption at very acceptable levels. The 9000 series have a soldered heat spreader, and that works out well with the 9600K.
With this six cores and threads proc you get a 95 Watt TDP processor. With the system at idle with a GeForce RTX 2080 Ti installed / 16 GB memory / SSD and the Z390 motherboard, I hovered at roughly 50~60 Watts in IDLE. That's just fine and normal really, the load values are okay as well. When we stressed the processor 100% run we reach roughly 125 Watts with this 6-core part. That's the entire system. Overall, I have no worries here.
For Coffee Lake-S (8th and 9th Gen Intel procs) and DDR4w e always say, volume matters more than frequency. A 3,200 MHz kit, for example, is more expensive and does offer better bandwidth but the performance increase in real-world usage will be hard to find. Unless you transcode videos over the processor a lot. As always, my advice would be to go with lower clocked DDR4 memory with decent timings, but get more of it. Don't go for 8 GB, get two or four DIMMs and in total a minimum of 16 GB. The reason we test at 3200 MHz is simple, we do the same for AMD Ryzen and want to create a fair and equal playing ground for both. 3200 Mhz is, however, a very nice equilibrium for both processor brands.
Performance & tweaking
We tested multiple Z390 motherboards all with the latest BIOS. I'd rate the 9600K 6-core processor as 'very good' for gaming, and a bit more normal for your typical threaded applications. It puzzles me as to why Intel did not simply enable Hyperthreading, as it would have been far more serious to be able to compete with say a Ryzen 5 2600X. Then again, Intel would be cannibalizing its own 8700K product positioning. Temperatures are totally fine under default circumstances and clocks frequencies. Once tweaked we noticed that the six cores like a bit extra voltage, we expect all-core tweaks in the 5 to 5.2 GHz marker to need 1.30V with higher tweaks in the ~1.35 Volts ranges on the processor. While that does increase power consumption, it wasn't something that scared me away. Temps at such voltages reach the 70 Degrees C marker. We, however, did use an ES sample and did use LCS cooling. If you plan a tweak at that 5 GHz marker then remember my remarks on cooling, you will need LCS, that or a very good heat pipe cooler. The infrastructure that Z390 offers is easy to use, you increase the CPU voltage and multiplier and you are good to go. Another plus for the Intel platform is that over the years they have been able to refine their memory controllers, pop in anything XMP 2.0 and you have a 90% chance it'll work straight out of the box with very fast memories. Mind you that all our tests are performed at 3200 MHz DDR4, similar to Ryzen and Threadripper to remain objective and for fair play on both sides. realistically though, Ryzen is more memory frequency dependent in gaming than Intel is.
While testing the Core i5 9600K the multi-threaded performance was a bit lack-luster, this proc really could have used SMT (Hyper-threading). However, Intel carefully examined the Achilles heel of Ryzen processors and realized that with (and only) very expensive graphics cards they can perform much better by tightening up the number of instructions per clock cycle. For gaming it is simple, six cores clocked at a higher frequency works out better than six cores with twelve threads clocked at a lower frequency. And that makes this processor the golden egg when it comes to gaming. While writing this review I had not received pricing just yet, but expect the Core i5 9600K to sell at roughly $279. However I do need to make a side note, as 14nm production is limited, and that drives up prices. We have no idea what the final retail price will be due to upcoming and pending shortages. This processor performs at a threaded application level of the AMD Ryzen 5 2600, and that processor is just 199 USD. When i reverse that and look at the pricing, realistically it sits in Ryzen 7 2700 / 2700X territory. Threaded performance wise in all instances Ryzen is the faster product. However, for gaming combined with extremely fast graphics cards, that picture is reversed as the Core i5 9600K simply delivers fantastic results there. Yep, six-cores is the new four cores. Quad-core processors have become last years news on the gaming desktop platform. Everything ran pretty much as expected with expected perf, gaming wise the 9600K will excel if you give it a fast enough GPU. It is in that mindset that I am stating this, value for money wise this might be the best gaming CPU to get in the enthusiast class gaming range. As such we can certainly recommend it.
Handy related downloads: