This power supply complies with the ATX12V 2.0 standard. The maximum load on the +12V rail can be as high as 36A (432W). The +12V2 line is a separate item in the last line of the label where the combined allowable loads are specified, although the +12V power rail is split in the W0057 in the traditional “virtual” way, so it doesn’t matter for the PSU which line, +12V1 or +12V2, is loaded if the combined current in them is below 36A. These lines aren’t connected with the +5V and +3.3V lines, so I don’t grasp the purpose of specifying a combined load for the +3.3V, +5V and +12V1 lines.

The power supply has no problems outputting voltages under any permissible load, but unfortunately its cross-load characteristic isn’t perfect despite the independent regulators. The +12V voltage is set so high that it is close to the acceptable limit of 12.6V under zero load. At the maximum load it is still 3% above the nominal value. The +5V voltage is very high, too, but is also not very stable: the graph changes from a precise coincidence with the nominal to a 5% deflection which is a rather poor result for a power supply with independent voltage regulation. Of course, the W0057 looks good against many other models, but I had hoped to see some better results from it.

At max load the output voltage ripple was 35 millivolts on the +5V rail and about 65 millivolts on the +12V rail (the allowable maximums being 50 and 120 millivolts, respectively).

I disabled the manual control unit before measuring the fan speed. Alas, the PSU is far from quiet. The fan starts off at a speed of 1200rpm and quickly accelerates as the load grows, reaching 2000rpm under a load of less than 200W. You can compare this result with those of really quiet power supplies like the Zalman ZM460-APS (460W) or the Seasonic S12 SS-500HT (500W) where the fan speed is a little over 700rpm initially and is not higher than 1500rpm even at the max load.

The efficiency of this PSU is low by today’s standards, reaching only 77% at the maximum. It’s no better with the power factor which barely reaches 0.95 while PSUs with active power factor correction typically have a power factor of 0.98-0.99.

I can’t say the W0057 is bad, but it is rather expensive for ordinary users (it is selling in retail stores for about $100) and unexciting for PC enthusiasts with the parameters it has. The PSU is rather noisy at work and this cannot be cured by the manual controller – it doesn’t allow reducing the speed of the fan below 1200rpm which actually seems to be very close to the bottom limit of stable operation of the powerful fan employed in this PSU. This speed controller is also useless for a second fan because a rather powerful model is included with the PSU and you cannot slow it down to below 1350rpm. It can only be replaced with Thermaltake’s fans explicitly supporting such speed controllers. The selection of such models isn’t large and includes only powerful models with a high maximum speed, and you can’t slow them down to silent level, either. So, if you need a quiet power supply, you should consider other models. Even lacking a manual fan speed controller, many of them are quieter than the W0057 but cost the same or lesser money.