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Bitfenix Unveils The Whisper PSU Line

Bitfenix enrolled in the PSU market a couple of years ago with the Fury Gold units, which had a nice looks and featured quality, individually-sleeved cables but cost a lot, and their FSP platform didn't offer high enough performance. It seems that Bitfenix hasn't forgotten about the PSU market, though, and is looking to make a strong comeback with the Whisper line, which is made by a different OEM now--Channel Well Technology (CWT).

The members of this line cover a wide wattage range, from 450W to 850W, with 100W increments. All are fully modular and 80 PLUS Gold certified, while their CWT platform with code name "GPU" promises high performance, increased reliability, and silent operation. After all, the Whisper units have to honor their name. so they cannot be noisy under any usage scenario.

The two entry-level models of the line with 450W and 550W capacities have three +12V rails, whereas the 650W, 750W, and 850W Whisper units feature four +12V rails. At their internals, you'll find Japanese capacitors and an HDB fan, provided by Martech, which is rated for a pretty low lifetime of only 30,000h at 25°C. Bitfenix covers the Whisper units with a long seven-year warranty, so it's highly confident about the longevity of both the fan and the platform. Further, all necessary protection features are supported, including OTP (Over Temperature Protection).

The "GPU" platform is new, and the Whisper units are the first ones to use it. Bitfenix made some minor modifications to this platform, including a set of custom heatsinks for the +12V FETs, which won't be available to other companies that will be interested in using this CWT platform as well. In order to keep the production cost low, Bitfenix didn't equip the Whisper units with special modular cables, like it did with the Fury Gold line. However, you can purchase Bitfenix's Alchemy 2.0 cable kit, featuring the highly desired (by case modders, mostly) individually sleeved cables. We should mention here that only the 24-pin ATX connector uses three polymer caps for providing an extra ripple filtering layer, while all the rest cables don't have any caps attached.

If you plan to power a high-end mainboard that needs more than a single EPS connector, then the two stronger Whisper units are the ones to go after, because they come with a couple of 4+4 pin EPS connectors. All the lower-capacity models of this line are equipped with only a single EPS connector.

OEMChannel Well Technology
ModelsBWG450M, BWG550M, BWG650M, BWG750M, BWG850M
DC Output Range450W - 850W
Efficiency80 Plus Gold
ModularYes (fully)
Intel Haswell ReadyYes
Operating temperature0°C ~ 50°C
ProtectionsOver Voltage Protection Under Voltage Protection Over Current Protection Short Circuit Protection Over Power Protection Over Temperature Protection
Cooling135 mm Hydro Dynamic Bearing Fan (DF1352512SEMN or DF1352512SEHN)
Semi-passive operationNo
Number of PCIe (6+2 pin) ConnectorsBWG850M, BWG750M: 6 BWG650M: 4 BWG550M, BWG450M: 2
Number of EPS ConnectorsBWG850M, BWG750M: 2 BWG650M, BWG550M, BWG450M: 1
Dimensions150 mm (W) x 86 mm (H) x 160 mm (D)
ComplianceATX12V v2.4, EPS 2.92
Warranty7 years
MSRPBWG850M: $119 BWG750M: $109 BWG650M: $89 BWG550M: $79 BWG450M: $69

We have already evaluated two members of this line, and the results were good. Given the fairly affordable MSRPs that Bitfenix set for these units, their performance per dollar ratios hit really high levels, making them ideal for users that are after good deals. The MSRPs are provided in the table above.

The following tables show the power specifications of all Whisper units.

BWG450M Power Specs
Max. PowerAmps20202525252.50.3
Total Max. Power (W)450
BWG550M Power Specs
Max. PowerAmps20202525302.50.3
Total Max. Power (W)550
BWG650M Power Specs
Max. PowerAmps2020252530302.50.3
Total Max. Power (W)650
BWG750M Power Specs
Max. PowerAmps2222252535352.50.5
Total Max. Power (W)750
BWG850M Power Specs
Max. PowerAmps2222252540402.50.5
Total Max. Power (W)850

As we already stated, the lower capacity units have three +12V rails, whereas the 650W, 750W, and 850W Whisper members feature four of them. Besides the capacity of the minor rails, there is also a small difference in the capacity of the -12V rail--a useless rail for modern PC systems, which is a little stronger in the top two Whisper models. Finally, in our opinion, the 5VSB rail should be a little stronger in the higher-capacity Whisper units and not be confined at 2.5A max current output.

Expect the new Bitfenix Whisper PSUs to be available on the U.S. market in a few days from now, on December 5.

Aris Mpitziopoulos
Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.