The new PicoPSUs

PSUs: The source of DC power for all components in the PC & often a big noise source.

Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee, Devonavar

Post Reply
bean1975
Posts: 90
Joined: Thu Jan 12, 2006 3:46 am
Location: Vancouver

The new PicoPSUs

Post by bean1975 » Wed Jan 24, 2007 5:16 pm

At Mini-box.com I saw PicoPSU-120-WI-25V with a 12-25V input and PicoPSU-120-WI-32V with a 12V-32V input. I checked the WI-25V manual and it says 6A over 12V which is more than enough for a mobile on the desktop. And you no longer need to hunt for arcane high ampere 12V bricks, any run of the mill laptop charger will do -- I think the sweet spot is at 19V. 19V 6.3A (120W) laptop chargers are twelve a dozen. And smaller, 4.74A (90W) chargers also equally easy to be had.

jimmyfergus
Posts: 89
Joined: Tue Sep 07, 2004 8:24 am
Location: MA, USA

Post by jimmyfergus » Thu Jan 25, 2007 7:28 am

Please forgive a question without much research, but how do I work out my 12v amperage requirement? I assume the CPU, HD & optical all draw mainly from the 12V? I have:
  • X2 3800+ 65W, should use well under 65W, but a theoretical max of 5.5A if it took that all from 12V
  • 3.5" Samsung SATA drive, up to 1A?
  • DVD drive ???
If they all draw from the 12V line, I would be done for, especially given that I can't undervolt in BIOS, so at startup I'm drawing full power?

I have an NSK2400, and the PSU whines, so a replacement is attractive...

jimmyfergus
Posts: 89
Joined: Tue Sep 07, 2004 8:24 am
Location: MA, USA

Post by jimmyfergus » Thu Jan 25, 2007 7:35 am

I should have read more first... I see they say it isn't to be used with 3.5" drives or full-size CD-ROMs...

drees
Posts: 157
Joined: Thu Jul 13, 2006 10:59 pm

Post by drees » Thu Jan 25, 2007 11:39 am

Those look interesting, they take a small efficiency hit because of input voltage range (now it has to regulate the 12v output), I wonder how the efficiency varies based on input voltage...

I wonder why they built both a 12-25v and a 12-32v model when the specs are otherwise similar?

jimmyfergus
Posts: 89
Joined: Tue Sep 07, 2004 8:24 am
Location: MA, USA

Post by jimmyfergus » Thu Jan 25, 2007 11:44 am

I see the one 12-32V costs more and has lower efficiency, so there is a tradeoff.

From a business perspective, I would have thought they should just sell the 12-32V to keep their manufacturing and catalog simpler. It's nice for us to have the choice though.

drees
Posts: 157
Joined: Thu Jul 13, 2006 10:59 pm

Post by drees » Thu Jan 25, 2007 12:17 pm

jimmyfergus wrote:I see the one 12-32V costs more and has lower efficiency, so there is a tradeoff.
Well, 1% efficiency and $2 isn't that much of a tradeoff, IMO!

jojo4u
Posts: 806
Joined: Sat Dec 14, 2002 7:00 am
Location: Germany

Post by jojo4u » Thu Jan 25, 2007 3:14 pm

You guys forget about the to 12 V conversion. The original PicoPSU didn't touch the 12 V line.

EDIT: of course, dreed mentioned it first. See my message as a reminder that's more than a 1 % hit.
Last edited by jojo4u on Fri Jan 26, 2007 5:12 am, edited 1 time in total.

drees
Posts: 157
Joined: Thu Jul 13, 2006 10:59 pm

Post by drees » Thu Jan 25, 2007 3:48 pm

jojo4u wrote:You guys forget about the to 12 V conversion. The original PicoPSU didn't touch the 12 V line.
I didn't forget, I mentioned it in the 4th post of this thread.

SnooP
Posts: 106
Joined: Mon Nov 28, 2005 1:01 am

Post by SnooP » Thu Jan 25, 2007 11:45 pm

jimmyfergus wrote:Please forgive a question without much research, but how do I work out my 12v amperage requirement? I assume the CPU, HD & optical all draw mainly from the 12V? I have:
  • X2 3800+ 65W, should use well under 65W, but a theoretical max of 5.5A if it took that all from 12V
  • 3.5" Samsung SATA drive, up to 1A?
  • DVD drive ???
If they all draw from the 12V line, I would be done for, especially given that I can't undervolt in BIOS, so at startup I'm drawing full power?

I have an NSK2400, and the PSU whines, so a replacement is attractive...
Try my psu calc, has 12V amps calculations.

http://web.aanet.com.au/SnooP/psucalc.php

Post Reply