Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I need a compact power supply unit, but I don't know which picoPSU to buy to feed a Gigabyte GA-GC230D mini-IT motherboard + a 3.5" hard-disk, and a DVD burner used occasionally.

For the DC unit, would 90W be enough, or should I go for 120W or 150W?

What about the external AC adapter (60, 80, 102W)?

share|improve this question
And I read "how much power to feed TheTXI"... I'm tired. – Gnoupi Aug 31 '09 at 11:58
up vote 1 down vote accepted
  • Atom 230 = 25W
  • DVD < 25W
  • HDD < 30W

80W total. Lets say the PicoPSU is 80% efficient. No 90W will not be enough. 120 W will give you some headroom. You might want to consider Flash memory instead of a HDD; it will you a lot less power.

share|improve this answer
Thanks for the infos. Do regular Linux distros work fine with Flash memory today, or do they still require some kung-fu like putting /tmp in RAM to reduce write accesses to a minimum? – OverTheRainbow Sep 1 '09 at 11:34
Check out Easy way to craete a USB-bootable installation of several different distros. – hometoast Sep 1 '09 at 19:24

I'd certainly go for a larger one than you think you need. You could end up blowing an underrated PSU if everything is in use (HDD & DVD when installing or burning for example).

Another thing to bear in mind is that the various components might draw slightly more power than their rated values.

share|improve this answer

Regardless of rated draw, also keep in mind that if everything is idle, the PSU isn't pumping it's max output, either.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.