Intel 9th-gen Core i9-9900K Review: The 'best gaming CPU' is also the fastest

Intel says its 8-core, 9th-gen Core i9-9900K is the "world's best gaming CPU," but it's wrong. It's easily the world's fastest gaming CPU.

Credit: Gordon Mah Ung

Core i9-9900K Performance Analysis

To close out our performance testing, we like to use Cinebench R15 and increase the load from one thread to many on the various CPUs. First up is the Core i9-9900K vs. the Core i7-8700K. The results clearly show the 6-core Core i7-8700K can’t hang with the new Core i9-9900K at any level.

9900k thread scaling vs 8700k IDG

The Core i9 gives no quarter to its sibling, the Core i7-8700K.

One problem with the chart above is you can’t get a feel for the scale of the performance difference, so we ran the numbers for you. As you can see, at low thread loads, the Core i9 is running at higher clocks than the Core i7, with 7 percent to 10 percent more performance. Where the Core i9 really opens up a Costco pallet’s worth of oomph is beyond 8 threads.

9900k thread scaling percent vs 8700k IDG

,The Core i9 has a 7- to 10-percent advantage on light loads, and opens up to 31 percent and 44 percent on heavier loads over the Core i7-8700K.

This isn’t about blue-on-blue, though. Intel is clearly aiming AMD, so let’s see how the Ryzen compares. As you can see below, the Core i9 gives up no quarter.

9900k thread scaling mce off IDG

Intel’s Core i9 is simply a beast.

As we did above, let’s how that translates into percent increase of a Core i9-9900K over a Ryzen 7 2700X. One weakness of the Ryzen 7 2700X has always been on lighter loads. Where the Core i9 only has a 7- to 10-percent bump over the Core i7, it’s into the double digits with Ryzen 7 2700X. It’s basically 20 percent faster at all loads up until 11 or more threads. On stock settings, the Core i9 falls back to about 4.3GHz to 4.2GHz, which makes it closer.

9900k thread scaling percent mce off vs 2700x IDG

The Core i9 outpaces the Ryzen 7 2700X by 20 percent-plus on light loads.

But that brings us back to the original thorny question of MCE. MCE is available on motherboards as cheap as $130. One could argue that board may push it as hard as the pricey Maximus XI Hero we’re using here but if you have a decent motherboard, it’s likely you’ll get a decent bump out of MCE. And with MCE on, as you see below, the Core i9-9900K is simply a monster. 

9900k thread scaling percent mce on vs 2700x IDG

With MCE on, the Core i9 is 30 percent faster than an 8-core Ryzen 7 2700X.

Conclusion: Core i9-9900K is actually worth it

We’ll be honest, we were pretty skeptical of Intel’s Core i9-9900K. After all, with an 8-core Ryzen 7 1700X at $329 (and $300 on the street), which includes a decent cooler, what’s Intel thinking, pushing an 8-core Core i9 chip for $488 ($529 on the street) without a cooler?

Sure, we accepted the Core i9 would be faster. After all, it’s 8 cores with a Turbo Boost of 5GHz. But damn, $529? Once you toss in a decent cooler, you’re looking at $580. The price differential is enough to buy a decent graphics card, a lot of RAM, or a big SSD.

But seen in the light of our performance testing, we can now say the Core i9-9900K is definitely worth the stretch for performance fiends. The Core i9-9900K is simply a monster of a CPU that can easily claim the title of being the fastest mainstream CPU and the fastest gaming CPU. That’s just not something that comes cheap.

intel 9th gen core 13 Intel

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Gordon Mah Ung

PC World (US online)
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