1

Recently I bought a device to measure the wattage from devices. To test the apparatus I measured 6 watts from an IKEA LED light bulb which was supposed to produce 6 watt usage and a few laptop adapters. The apparatus seems to work.

Then I tested my work in progress home server. It surprised me the server demanded 25 watts while it was turned off. So I searched some and it appeared normal for desktop machines to demand some wattage for a bunch of functions like waking up the desktop through LAN. Though 25 wattage seems an awful lot.

Then I turned off the power button on the power supply so I could no longer turn on the server. I would suspect 0 watts to be demanded, instead, a steady 13 watts is demanded by the desktop.

I tried all sorts of BIOS shenanigans to be found on the internet to reduce wattage while the server is off. I can't seem to get below the 25 watts.

What is going on? So far the only idea as to what could be the problem is a faulty power supply which is making an internal short circuit or something.

What can I do to make wattage usage acceptable (~5 watts) when I turn off the server?

Some pictures as to my current setup and bios settings:

enter image description here

The power supply is a Cooler master RS-520-ASAA-A1.

Improve this question
4
  • It would be easier to use hardware that did this. There are specific products that prevent "vampire power usage". Outside of those products there really isn't much you can do about it. Your hardware is working within their specifications its your expectation that are faulty.
    – Ramhound
    Commented Mar 9, 2015 at 17:24
  • If you detach the PSU from the computer, does it still draw 13W when off?
    – Ƭᴇcʜιᴇ007
    Commented Mar 9, 2015 at 17:31
  • 1
    Yes, PSU only (without connections to the computer) still draws 13 when turned off.
    – InteressantPunt
    Commented Mar 9, 2015 at 17:34
  • Unless you’re fully equipped with ErP Lot 6 devices, you can never achieve acceptable standby power consumption. Even though the EU took away our proper vacuum cleaners, it also has its good sides. ;)
    – Daniel B
    Commented Mar 9, 2015 at 17:35

1 Answer 1

Reset to default
0

So I mailed the manufacturer and the 13W is indeed too high and unexpected. Most consumer wattage measurement devices measure Volt-amps which is different then wattage.

Turns out the PSU consumes 3.9 watts, while consuming 21 VA, explaining the difference.

Improve this answer

Not the answer you're looking for? Browse other questions tagged .