Be quiet! has developed a unique platform with Channel Well Technology for the Pure Power 11 FM line and the results are impressive. With a capacity of 550W, the Pure Power 11 FM is our top choice in this wattage category and one of the best power supplies for gaming (opens in new tab).

This PSU is 80 PLUS Gold and Cybenetics Gold efficiency certified and has a Cybenetics A noise rating, proving it is quiet. Dimensions are standard at 160 mm deep, and the cooling fan has rifled bearings for reliability; the 5-year warranty is shorter than that of competing products (e.g., Corsair, RM550x). Still, it is not short.

CWT platforms generally have better soldering quality. Our main objection is the use of 85°C bulk caps when competitors use 105°C caps. Elite caps on the secondary side are the best alternative to Japanese caps, which are now hard to find and extremely expensive. Finally, the low speeds use rifled bearings, which should be fine within the warranty period (and even longer).

There are two 12V rails that can supply up to 550W total, and the minor rail can supply up to 120W. The standby rail is also powerful enough, with a maximum current output of 3A.

The ATX cable could be longer. The same goes for the single EPS cable. Also, there should be one EPS and one ATX12V connector instead of one EPS; the FDD connector could be increased to three by replacing it with a 4-pin Molex.

The 12V load regulation is satisfactory, the other rails are tight, and ripple suppression is excellent!

Hold-up time is noticeably longer than the 17ms required by the ATX specification, and the hold-up time for the power OK signal is closer to 16ms. Inrush current is low at 115V and high at 230V.

It must be said that this is a high-efficiency platform: 5VSB rail efficiency is there, vampire power is low. Average efficiency is high, even for gold rated units.

Transient response voltage deviations are low on all rails and PWR_OK delays are in the 100-150ms range, so the PSU supports another low power mode recommended in the ATX specification.

The OCP trigger point for the first 12V rail is high and the OCP trigger point for the second rail is high; setting the OCP high is logical for a low-capacity PSU to avoid power spike issues, given that the platform can handle such a high power load It is logical for low-capacity PSUs to avoid power spike problems. On the other hand, overpower protection is set conservatively. In general, overstressing the power supply is not ideal. If more power is needed, purchase a more powerful power supply unit.

As for noise, the Be quiet! units live up to their brand name, but the Corsair RM550x (2021) is even better.

Be quiet! has a long history of producing quiet products and power supplies. The brand may not be as popular in the U.S. market, where it is a major player, but it is catching on in its country of origin, Germany, and with a product like the Pure Power 11 FM 550, it will not be hard to quickly gain worldwide popularity.

The Pure Power 11 FM 550 has shown that it has no problem competing fiercely with the likes of Corsair, Seasonic, EVGA, and Cooler Master.