An alarming trend we noticed with our roundup was that power supplies with fan controls on the rear of the unit have problems keeping tight tolerances.  We looked into the problem a little more and noticed that while the components on the inside of the unit were of good quality, the fan control switches themselves were not. 

Often the worst cases were fan control power supplies with often poor locking mechanisms.  For example, the TTGI power supplies sometimes let the control switch slip slightly, resulting in a switch that rested half way between “high” and “low”.  As a result, the poor contact produced incredibly awful ripple tests as demonstrated below.

Fan Control out of Place Voltages

 

+12V Low

+12V High

Kingwin KWI-450WABK

11.830

12.225

TTGI/SuperFlower 520SS 4Fan

11.820

12.240

TTGI/SuperFlower 420SS

11.850

12.225

TTGI/SuperFlower 350SS

11.875

12.305

Vantec Ion 400W

11.780

12.005

Vantec Stealth 520W

11.750

12.010

Edit:Although these measurements do not show the +12V rail out of specification from the ATX12V 1.2 document, they are much different from the measurements obtained on the previous page. This change warrants some attention, since if unchecked, poor signals will damage your hardware.  Newer motherboards attempt to purify signals coming on the motherboard to prevent catastrophic failure, but voltages over the rails not feeding to the motherboard are very susceptible to failure (this puts a video card or hard drive in serious jeopardy). 

After contacting manufacturers with this information, we got confirmation from companies stating that they planned on dropping the fan control from their power supplies.  Vantec told us that dropping this controller actually lowers their cost significantly, and the savings would be then relayed to the consumer.  Consider how much you actually use the fan control on your power supply (if you have one).  Our opinion is that the tradeoff will be well worth it.

Voltage Testing Final Thoughts
Comments Locked

70 Comments

View All Comments

  • Anonymous User - Saturday, August 2, 2003 - link

    #11, yes P=IxV, but the power ratings in the table were obviously taken from manufacturers' data rather than actual measurements, which is why when any power rating for any of the positive voltages is divided by that voltage, the quotient exactly equals an integer. That would not be a problem if all manufacturers applied identical standards to their specifications, but many computer users have learned that this isn't the case.
  • Anonymous User - Saturday, August 2, 2003 - link

    Perhaps you could include a Q-Tec PSU in the next review? They retail here in Sweden at about 60% of the price of corresponding Enermax and other high quality units, so assuming they aren't totally lousy they're very cheap.
  • Anonymous User - Friday, August 1, 2003 - link

    I agree with #15. Definitely take a look at the PC Power and Cooling 400w Silencer PSU. I own two of these units and they're very high quality with reasonably low noise.
  • Anonymous User - Friday, August 1, 2003 - link

    Enlight power supplies are always being excluded from these PSU comparsions. I have a Enlight 360W PSU and it's very stable and very quiet. Test some Enlight PSUs!
  • Anonymous User - Friday, August 1, 2003 - link

    I appreciated the comments concerning AMD users, but what I really need is some sort of guidance on AMD processor speed vs combined power or 3.3V rail current for upgrading older systems. Many older cases have limited power supplies and I'm trying to figure out the fastest processor I can install and still have reliable operation. Example: A 300 watt supply with 25A of 3.3V can only support up to a Athlon 1600+ on an ECS K7S5A Pro or a 350 watt with a combined power of 200W can support up to 2200+. Oh, and forget that old 250 watt power supply altogether. I need something like that... yeah, I know: your mileage may vary, void where prohibited by law, no watts were endangered in the making of this article.....:-)
  • Anonymous User - Friday, August 1, 2003 - link

    Next time you guys might want to check out the PC P&C Silencer 400. It's built just as heavily as the Turbo Cool but with a quieter fan.
  • Anonymous User - Friday, August 1, 2003 - link

    Hey guys, im sure 1 or 2 of you resistorheads are an ee or will soon be one.. ripple and noise are only part of a good pwr supply.. we need the facts... how many watts do these power supplies really put out. how do they respond with a big load.. will they take an overload.. how well are they protected...thats what i wanna read about
  • MIDIman - Friday, August 1, 2003 - link

    WOW - excellent review. I'm getting a zalman for my silent box.

    Nice to see you guys pumping out articles quickly again! Thanks!
  • idenyit - Friday, August 1, 2003 - link

    hey just wondering the allied A400ATX hows that compare with the B400ATX thats offered on newegg? any differences?
  • Anonymous User - Friday, August 1, 2003 - link

    #10, doesnt P=IV? The Power and Voltage measurements were given.

Log in

Don't have an account? Sign up now