550W-650W PSU Roundup 2014

Be Quiet! Power Zone 650W Review

Manufacturer: be quiet!
UK: £78.78 (inc VAT)

German PSU manufacturer Be Quiet! uses variations on the theme of ‘power’ to label its various product series. The affordable 80 Plus Bronze line carries the moniker Power Zone and we tested the 650W version, the entry-level model in a line-up that also contains 750, 850 and 1,000 watt editions. The actual manufacturing comes courtesy of FSP, that also designed these PSUs, although Be Quiet! claims to have added some optimisations of its own.


The design is single-rail and the 650W version offers 54A on the 12V rail. The Power Zone 650W comes with modular cabling and a reasonable amount of connectors: four molex, eight SATA and four 6/8-pin PEG. This makes it fully compatible with SLI and Crossfire, although we would not recommend hooking up more than a couple of mid-range graphics cards to a 650W PSU. Also worth a mention is that most of the cables on the Power Zone are the longest of their kind in this test, with just the PEG cables falling short at a “mere” 57cm (22.5 inches). Cooling comes courtesy of a 13.5cm (5.3 inch) Be quiet! Silent Wings fan, with a variable rotation speed based on temperature.

Looking at the test results, we are anything but disappointed. The Power Zone 650W delivers stable voltages with a low ripple, while the measured efficiency is nothing to be ashamed of, particularly in light of the fact that we’re talking about an 80 Plus Bronze PSU here. Efficiency peaks at 300W load at 88.68 percent. This is clearly the optimal workload for this PSU, as the noise production is also more than acceptable at this stage, measuring 30 dB(A). Once we increased the load to 500W, the Silent Wings fan proved to be not quite that silent, topping out at 48 dB(A).

In summary, you could do a lot worse than buying the Power Zone 650W, but the price is what keeps us from outright recommending it, given that cheaper and similarly priced units have just as good if not better performance and features.