Intel’s Core i9 9900KS has arrived – and it’s a beast. This $599 limited edition processor was created from the best-performing 9900K models and is advertised as running at an all-core turbo speed of 5GHz, right out of the box – something only a fraction of 9900K samples could hope to achieve through careful manual overclocking. The 9900KS should also be capable of hitting a given frequency at a lower voltage than most 9900K units in the wild, making it an ideal choice for enthusiasts that want to achieve their high clocks at low temperatures. Given how well the 9700K and 9900K perform in most games, the 9900KS should take the crown as the fastest gaming processor on the market with its faster all-core turbo and higher 127W TDP – but the question is whether it’s actually worth its higher price, when you can already get strong gaming performance from a range of much cheaper processors from AMD and Intel.
Before we answer that question with a selection of synthetic and game benchmarks, it’s important to qualify exactly what you can expect from the 9900KS. Right from the off, the advertised 5GHz all-core turbo figure is a little misleading. The 9900KS can indeed turbo to that frequency on all eight cores, but whether it will stay there depends on your motherboard. On the Asus ROG Maximus XI Extreme board we’re using with the ‘multi-core enhancement’ setting disabled, the 9900KS will hold that speed for about half a minute when faced with an all-core load, then throttle back down to a more reasonable frequency (eg 4.5GHz) to stay within its power envelope. With the MCE setting enabled, however, the chip’s power requirements are relaxed substantially, allowing the chip to remain in that 5GHz turbo period indefinitely, assuming adequate power delivery and cooling.
We think that most users considering the 9900KS will be using a high-end motherboard with similar options to relax power limits – including some that will be configured like this out of the box – so our game testing was conducted with MCE enabled and power limits relaxed. If you do buy this processor, remember to check your in-game frequencies with software like Riva Tuner Statistics Server to make sure that your processor is operating to its full potential. Conversely, if electricity is expensive where you live or your power supply isn’t up to snuff, you’ll want to keep MCE disabled to maximise efficiency – and if that’s the situation, you may be better off simply getting an existing Core i9 9900K or i7 9700K. F