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Silent 500W Power Supply

Posted by CmdrTaco on from the nice-juice-box dept.

NightRyder writes "To cope with the increased power demands of today's processors and video cards a 500W silent power supply has been released by Antec. The topic of silent power production has been an important one to the computer community recently, especially concerning the increased hardware demands by new game and operating systems. Considering the processing demands of something like, *cough* Windows Vista, its important to be able to keep your computer cool without it getting loud."

1 of 252 comments (clear)

  1. Re:"silent" by jepaton · · Score: 0, Troll

    Single power distribution would decrease power conversion efficency.

    The main PSU is a switching power supply, which is an efficient and cheap
    method of dropping from 120V/240V down to 12V. A large voltage drop and
    high current, the alternative is a BIG transformer weighing several kgs...

    Switching regulators are available, which can step down from from say 24V
    to 5V etc. Unfortunately, they are cost prohibitive and still will not
    provide the clean power required. Also, the lower the required voltage
    drop the less efficient they are.

    Linear regulators have the opposite efficiency curve, they get more
    efficient the lower the voltage drop required. Of course, they dispate ALL
    of the dropped voltage as heat. Pdispated = Iout * (Vin - Vout). If Vin
    is close to Vout then they are near 100% efficient.

    In a PC, the PSU provides voltages close to those that are required, and
    linear regulators are placed close to the components requiring the power.
    The linear regulators provide clean power but dispate a little as waste.

    For the battery/adapter powered product I am currently working on the
    cost difference between a switching regulator and a linear regulator is
    about 10 times.

    In summary, PCs are powered the way they are because it is the best cost/
    performance ratio. A single power-rail will be more expensive and less
    efficient.

    It would make sense if server power supplies could accept DC rather than
    AC. This would save the round tripping of AC (mains) to DC (battery) to
    AC (psu) to DC (computer). Telecomms has standardised on 48V, and it is
    possible to buy 48V DC PSUs. I bet you can get 48V dc UPS units too...

    Jonathan