Our testing methods
Here are the specifications of our test system:
|Processor||Intel Core i7-6950X|
|Motherboard||Gigabyte X99 Designare EX|
|Memory||32 GB (4x 8 GB) Crucial Ballistix Elite DDR4-2666|
|Graphics card||Gigabyte GeForce GTX 1050 G1 Gaming|
|Storage||Intel 750 Series 400 GB|
|Power supply||Seasonic Prime Platinum 1000 W|
|OS||Windows 10 Pro|
Our thanks to Gigabyte, Intel, and Corsair for helping us to outfit our test systems with some of the finest hardware available.
To test heatsink performance, we run the Blender "classroom" benchmark file three times in succession and report the median highest CPU package temperature observed in HWiNFO64. Blender is a demanding real-world workload that can still stress an overclock to failure. Prime95 Small FFTs generates a lot of heat, for sure, but the heat and power consumption it generates are both far in excess of any real-world application we've ever observed. As chips pack more and more cores into smaller and smaller die areas, they get harder and harder to cool to begin with, and it gets harder and harder to justify Prime95 as a representative workload.
Although some of our heatsink reviews have used Intel's massive Core i9-7980XE as a heat source, the fact that the latest Extreme Edition chip uses paste thermal interface material rather than solder under its heat spreader has bugged me while testing CPU coolers. We want our performance results to be limited as much as possible by the performance of the cooler under test, not the thermal transfer capability of a variable we can't control. With that in mind, I've set aside our X299 test rig in favor of the Core i7-6950X and its soldered heat spreader. At 4.4 GHz and 1.38 V, the ten Broadwell cores of the i7-6950X are still a formidable match for any cooler.
The ambient temperature of our testing environment was maintained at 72° F, plus or minus about 1° F, over the course of each test by monitoring with a calibrated thermometer throughout. We can't hermetically seal the office that serves as ground zero for testing in the TR labs, but this margin of error should help us understand whether the differences we're seeing between coolers are significant for the real world.
With our overclocked Core i7-6950X ticking away underneath, the H100i Platinum surprisingly chalks up a whopping 5° C delta versus the H100i Pro. Whether that's down to more cold plate area, a more effective pump, or some other factor, we can't say for certain. Given that we strenuously tried to control ambient temperature as a factor, however, the H100i Platinum's performance differences do appear to be significant versus Corsair's recent Asetek designs.
Despite the fact that these coolers use the same basic fan design, I noticed a stronger high-mid tonal component to the H100i Platinum's fan noise. That could be down to differences in radiators between the coolers, variance in fan production, or some other factor. To be clear, the H100i Platinum doesn't sound significantly worse than the H100i Pro. Indeed, its ML120 Pro RGB fans continue to perform a magic trick wherein they sound much quieter than the 53 dBA we recorded. Still, to my ear, the H100i Pro has a slight edge in the quality of its fan noise. Drop fan speeds to 1000 RPM or below, and these fans become inaudible.
Fan noise is just one component of a liquid cooler's aural signature at idle. The pump has a part to play, as well. The H100i Platinum's pump isn't silent at idle, but it's a higher-pitched and smoother sound than the rather growly and whiny signature that Corsair's latest Asetek pumps can make when running all out. It's also a hair quieter, as shown by our minimum-RPM noise tests. I still think it would be a killer feature for Corsair to use its coolant-temperature-monitoring smarts and allow its iCUE software to control pump speed automatically in response to temperatures, but that feature has yet to appear. If you're bothered by all-in-one pump noise at idle, the H100i Platinum is the best I've heard yet from Corsair. The company still has a ways to go to match the inaudible pump head on the Aerocool P7-L240, though.
The $160 H100i RGB Platinum is Corsair's flashiest and most expensive 240-mm closed-loop liquid cooler to date. That cost might seem high up front, but if you do a bit of math, Corsair isn't really squeezing customers for the price of this heatsink's RGB LED hardware. Consider that the H100i Pro carries a $120 suggested price, subtract the $35 list price of its included ML120 fans, and add back the $70 or so it would cost to acquire a pair of ML120 Pro RGB spinners at retail, and you arrive just a bit short of the $160 price tag the company wants for the Platinum version. That doesn't seem unreasonable to me at all, given that you're getting an integrated RGB LED lighting controller for the fans in the bargain.
On top of its good looks, the H100i Platinum pump does seem to carry heat away from the CPU better than the company's latest Asetek-powered designs, and it's both quieter and better-sounding at its highest speed setting than any of Corsair's Pro-series coolers. I'm not sure that performance and quietude is worth a 33% jump in price versus the H100i Pro, but if you're after the very best that you can get from Corsair, the H100i Platinum does seem to be it on the performance front.
All told, then, the H100i Platinum passes my test for any RGB LED-bedecked hardware. Form has to follow function, and the Platinum cooler delivers both better performance and sharper looks than its lower-end stablemates. If you want a capable high-end liquid cooler that can sync up with all of the advanced lighting effects possible with other Corsair hardware, the H100i Platinum is a strong choice for a fair price. Given its performance and features in this price bracket, I'm happy to call the H100i Platinum TR Recommended. If you're not invested in the Corsair RGB LED ecosystem and don't need the most capable blinkenlights, however, it'd probably be wiser to consider the H100i Pro or any of a multitude of more affordable liquid coolers.