In assessing game performance, I went with a smaller range of titles designed to show a range of different CPU profiles, from games that favour single-core power to one of the best multi-threaded game engines I've seen in recent times. There's also a prevailing feeling that 60fps gaming is a relatively easy target for most modern CPUs, something I wanted to test. While that is the case for most titles, there's a bunch I've played where this palpably isn't true. In essence then, buying a higher-end CPU is more about buying extra overhead for edge cases, as opposed to running the chip flat-out 100 per cent of the time.
In terms of those stress test edge cases, the truth is that Crysis 3's jungle levels can see Ryzen 7 2700X dip beneath 60fps (i7 is generally fine) and the original Crysis's Ascension level can tank an 8700K running at 5.0GHz to 40fps or lower. However, the point is equally proven with the much more modern Kingdom Come Deliverance on its ultra high setting - as you will see. Real-time strategy titles can also dip beneath 60fps, whether it's the Total War series or our first test case, Ashes of the Singularity.
Ashes of the Singularity
Ashes of the Singularity Escalation's CPU test takes graphics out of the equation completely and stress-tests the processor with a simulation that the developer tells us is very much representative of game performance - just what I want from a benchmark. "The CPU benchmark is four AI players playing each other in a large map," Oxide's Dan Baker tells us. "If you do a four-player game on a large map, it can eventually get to a battle that's this complex (I've seen larger and more complex battles). It's about as realistic as we could make it without putting a human in the mix. The only 'hack' we do is turn off unit deaths to keep the unit count more constant."
It's also remarkably punishing on the CPU to the point where even the 9900K cannot sustain a 60fps average, even running with enhanced turbo active. This is the Escalation variant of the game, which was updated to better support Ryzen processors, but even in a title that prides itself on multi-core utilisation, the 8700K is 12 per cent faster than AMD's offering despite its two deficit, while the 9900K has an 18 point lead over the AMD competition. It's interesting to note that the Z board's enhanced turbo has little impact in both cases, and in the case of the 9900K, the Asus board didn't lock to the max single-core turbo - all games tested here moved into margin of error boost as a result.
Ashes of the Singularity: CPU Test
Forza Horizon 4
Our first proper game test is Playground Games' Forza Horizon 4. Yes, we're using the benchmark, but it's a properly good one based on simulation of actual gameplay, with the underlying technology itself possessing supremely impressive across-the-board core utilisation. That said, even with an RTX 2080 Ti at 1080p resolution, the Core i9 9900K cannot improve upon the performance delivered by an 8700K, with 1440 and 4K differentials moving into margin of error.
The detailed report at the end of the benchmark helpfully confirms that we're barely CPU-bound at all in any of these tests on any of these processors - even with an RTX 2080 Ti running at just 1080p resolution, though Ryzen consistently lags just a few points behind the Intel competition. This is a good example of how a well-optimised title can deliver excellent performance across both Ryzen and Core architectures.
Forza Horizon 4: Ultra, 2x MSAA
Assassin's Creed Odyssey
This is one of the most demanding modern games we've tested in recent times, with Ryzen 7 struggling to stay north of 60 frames per second, while mainstream gaming CPU champ - the Core i5 8400 - has similarly struggled. The benchmark sequence in Assassin's Creed Odyssey is fascinating in that the 9900K can only deliver a three per cent improvement over the Core i7 8700K, but curiously, that advantage is sustained at all resolutions.
Ryzen 7 is in the mix here, but the main point of differentiation here is in the stutter, represented by the lowest one per cent and five per cent scores. This is an accumulation of the lowest frame-times throughout the entire clip, averaged and converted into frame-rate. It's poor on the AMD side at both 1080p and 1440p, but clears up at 4K. This is noticeable in gameplay, outside of the benchmark run tested here.
Assassin's Creed Odyssey: Ultra High, TAA
Far Cry 5
Based on the Dunia engine, the Far Cry titles on PC have typically benefited from fast single-core performance - something we've noted in Far Cry 4, Far Cry Primal and even this most modern of offerings. I've noted that overall core utilisation is wider this time around, but the fact remains that there's still clearly one dominant thread seemingly running the others. The end result is that - again, similar to prior games in the series - Intel offers a commanding lead over Ryzen. We can assume that we're almost completely CPU-bound at 1080p here, so percentage comparisons are valid - it's a 26.5 per cent lead for the 8700K, rising to 40.5 per cent on the 9900K.
As expected, the differentials close at higher resolutions as the GPU becomes more of a limiting factor, but Intel remains dominant, with only 4K resolution seeing everything move into line. Curiously, the 8700K's lowest one per cent scores spike here - when you are CPU-bound, stutter can be unpredictable, and it can happen to any of the three processors tested here.
Far Cry 5: Ultra, TAA
Intel Core i9 9900K analysis
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