The Corsair H170i Elite Capellix is a beast of an all-in-one liquid cooler. It offers top-tier performance, and while it may not take the #1 spot, it does quite well even in noise-normalized situations. In fact, its large size would likely make it a better fit for more power-hungry processors or higher overclocks, where its extra cooling capacity would likely result in a better showing. Even so, performance was good across the board with the H170i doing well on AMD and Intel platforms, which isn't always the case. Due to IHS designs differences between AMD and Intel processors, some coolers struggle on one but not the other. In this regard, Corsair has no problems. I imagine with a better mounting system that applies pressure on all four corners rather than in two spots via the clips, the H170i would see a slight improvement on AMD.

While noise levels are high when the fans are allowed to ramp up to full speed, it could be worse. How? Well, the fans are rated to spin at 400 to 2000 RPM. As noted in the RPM chart, the fans peaked in the low 1700 RPM range, a full 300 RPM short. Typically, +/- 10% is normal. That would mean 1800–2200. The fact that the fans topped out nearly 100 RPM below the typical range is worth noting. While this improved noise levels at the top end, it does mean our sample likely underperformed a bit in those tests where we allow it to run flat out. So it is a bit of a pro and con as the maximum noise level was not as bad, but potential performance was left on the table. Considering most don't want to listen to a leaf blower anyway, I wouldn't consider it a massive problem, although at this point, Corsair would likely have been better served just by limiting the fans to 1800 RPM and calling it a day.

Other than that, the cooler was easy to install—everything worked as it should, and even the iCUE software, which I am not a fan of, operated flawlessly. The inclusion of Zero-RPM fan mode is nice, and Corsair's design has built-in fail-safes for some peace of mind. Even so, call me old-fashioned, but I still prefer motherboard PWM control over yet another piece of software. The same goes for my ARGB synchronization; the motherboard software can be considered barely adequate, but the fact that I can synchronize all devices without proprietary kits is nice. I will commend Corsair for making the Commander Core and iCUE software work as well while including it all in the box, but it is an added cost that jacks up the price, which is sky-high to begin with.

Overall, the Corsair H170i Elite Capellix is a damn good performer that takes an already solid design and expands it to the limit. While gains are minimal, I would recommend it if you have the space for it; however, the vast majority of those looking at Corsair liquid coolers would likely be better served by opting for the easier-to-fit H150i, as 360 mm radiators are more widely supported in today's cases.