A very overclockable CPU with solid multipurpose performance, but AMD’s Ryzen chips offer better value in some areas
- More powerful than either of its Core i5 or Core i7 predecessors
- Six overclockable cores
- More expensive that AMD’s six-core CPUs
The entire lineup of Intel mainstream CPUs shifted with the launch of Coffee Lake. For starters, the fantastic quad-core Core i3-8350K costs under £200, making it the new budget gaming king, but the Core i5-8600K shakes up the range, too. While the Core i3-8350K is fine for most games, as well as typical tasks such as web browsing and streaming video, increasing numbers of applications now make use of more than four cores, and that’s where the Core i5-8600K really shines, as it brings six overclockable cores to the Core i5 range for the first time.
Its additional two cores effectively give it 50% more multithreaded grunt than both the new Core i3 and its predecessor, the Core i5-7600K. It’s the biggest change to Intel’s most popular K-series CPU in an age – the last time we saw an Intel core boost in this price league was with the Core 2 Q6600 ten years ago.
The new Core i5 has 9MB L3 cache compared to 6MB for the Core i5-7600K too, so it’s a beast by comparison. The only place the old CPU trumps it is with the base frequency, which is 200MHz slower. However, the maximum turbo frequency of the new CPU is 100MHz higher than its predecessor at 4.3GHz.
Price and competition
Price-wise, Intel has been shrewd, bumping up the price by around £100 compared with the Core i5-7600K, meaning the 8600K has a similar price compared to the old Core i7-7700K, leaving a huge gap between the new Core i5 and its baby sibling, the Core i3-8350K. However, the additional cores, plus the promise of good overclocking and gaming performance, means that it’s exactly the CPU Intel needs to battle the likes of AMD’s Ryzen six-core and eight-core CPUs, and offer a decent all-rounder again.
The higher stock base frequencies enjoyed by Intel’s Kaby Lake CPUs saw them edge out leads in our RealBench Gimp image-editing test, but amazingly, despite the fact they were both launched less than a year ago, they now occupy the bottom two places in our heavily multithreaded Handbrake video encoding test compared with the other similarly priced CPUs, and they sit equally poorly in the system score, too. The Core i5-8600K, on the other hand, managed mid-table results, but this situation soon changed once we overclocked the CPUs.
We managed to overclock our Core i5-8600K sample to 5GHz, with a VCORE of 1.34V, and this boost was enough for it to nearly match the AMD Ryzen 7 CPUs in the system score, with the latter still enjoying a commanding lead in the video-encoding test, but the Core i5 managed better results in our image editing, multitasking and gaming tests. The difference between Kaby Lake and Coffee Lake is stark, with the Core i5-8600K beating the Core i7-7700K in any tasks where its extra cores are used, and it even managed a higher RealBench system score, too.
CybertronPC – CLX SET Desktop – Intel Core i5-8600K – 16GB Memory – NVIDIA
The Core i5-8600K is a fantastic choice if you create content as well as play games, and it’s massively more powerful than either of its Core i5 or Core i7 predecessors. It’s a match for AMD’s six-core CPUs too, despite the fact that they offer more threads, although they’re considerably cheaper.
Similarly, AMD’s eight-core Ryzen 7 chips are much more powerful when it comes to multithreaded performance, and for less cash too, while the Core i7-8700K is the best option if you’ll be doing lots of multithreaded workloads. However, the Core i5-8600K is faster in games and lightly threaded workloads than AMD, especially when overclocked, making it a great multipurpose CPU.