Silent PSUs: Fortron Versus Silverstone

Efficiency

Efficiency plays an ever-increasingly important role in modern computers. Particularly with HTPCs designed to run constantly in living rooms, the high level of efficiency of the power supply ensures significantly lower electricity costs at the end of the year.

Overall, the Fortron power supply performed well. In the three load stages of the specification, the unit was constantly at over 84%. The best performance was obtained at below half load, where the efficiency increased to over 88%.

In our fictional system with a 250 watt load, the efficiency remained at a very good 87.7%, but in our low power system it only managed 76.3%.

In standby mode, with no load at all, the power supply only used 440 mW. With a standby load of just 2.5 W (500 mA at 5 V standby voltage) the Fortron converter drew 3.77 W from the socket, which is an efficiency of 65.5%.

The Zen 400 (PPA4000300) from Fortron (FSP) is available for a price of around $150.

  • knowom
    I think they'd be great for a digital audio workstation environment now if only there was some more competition in this market segment to drive prices down to a more decent level.
    Reply
  • mdmadph
    "The +12V CPU connection is only available as 4-pin version, which can lead to problems with some boards that require an 8-pin connection."

    Know of many HTPC boards that need an 8-pin CPU connection? :\ I sure don't.
    Reply
  • one-shot
    ^^lol
    Reply
  • I have read 3-4 other reviews of the zen 400W, and I'm pretty sure there has been no mention of the high pitched sound. It's not a good sign for the zen, but it's probably a faulty powersupply tested in this review.
    Reply
  • gwolfman
    Ummmm, so where's the temps? The review is practically pointless without temp measurements on a fanless PSU. BOOOOO!
    Reply
  • jeffunit
    Without specifying the input voltage, efficiency measurements are pretty useless. Running at 240v will yield a few percent higher efficiency than 120. Even 240v will be more efficient than 220v.
    Reply
  • kittle
    Re-run your review and include tempratures. Its pointless w/o them.

    If you have found a fanless PSU thats safe to touch -- thats great. but if these things get to 40, 50, 60c - then we need to know not to buy them.
    Reply
  • I own the Zen400 power supply and it's exactly what I needed for a quiet HTPC, to the point where it's literally impossible to tell when the PC is on. During normal operation I have never heard the high pitched sound this review mentions (although it did output a sound similar in volume and annoyance to a smoke alarm when I failed to plug in the power cable to the graphics card - it was clearly an error/failure tone).
    Reply
  • In regards to the lack of the 8 pin CPU 12v connector, if you can find a motherboard of which the 4 +12v pins of the port are not electrically connected, please point it out to actually justify needing the 8 pin connector. To be honest, a motherboard with a single +12v pin isolated to only 1 or 2 vcore phases would'nt be any motherboard you would want to purchase, for power efficiency reasons.
    Reply
  • Alternator
    I agree with the above posters, temps would be nice, and not just of the PSU...

    I am quite interested in getting a capable (above 400watt) PSU that doesn't require a fan, but I really need to keep an eye on the temperatures.

    I have a fanless mb and vid card (3850 radeon), and would wonder if adding a fanless psu into the mix would jeopardise the system by reducing the air flow through the case. (after all I wouldn't get a fanless PSU if my other components were noisy to begin with!?)

    Perhaps an article focused more on configuring a quiet computer (for the purpose of gaming) could be in order?
    Reply