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We have a user who's running off solar power, so she has certain limitations on how much she can draw. Traditionally we've given her a laptop and that has worked fine. However, with the new generation of mini-ITX and Pentium-M boards the day that we can give her a desktop cannot be too far off... or is it already here? Does anyone know if such a setup exists?

We're hoping to find a desktop/lcd monitor combo that draws not more than about 70 watts.

I think a mac-mini would work for us, but we don't want to go mac; for one thing she's in a remote location and supporting her on a new (to her) operating system would be a headache.

Thanks

Welcome to TR.

http://www.mini-itx.com/ might be a good place to start for small units.

The typical draw of a 17" Viewsonic monitor, for example, is 40w, so you're going to have to do some digging.

Edit: Looks like the Mac Mini has a maximum continuous power rating of 85W.

Would a desktop work? A high efficency power supply combined with an undervolted, possibly underclocked, (mobile?) CPU might be a viable option.

http://www.silentpcreview.com/

Take a look at the idle graph towards the bottom:
http://www.silentpcreview.com/article169-page3.html
Note that undervolting and underclocking would reduce it further. Also newer Athlon 64 CPUs reduce power consumption even more due to better manufacturing process. http://techreport.com/onearticle.x/7417

What notebook is she currently using? I doubt it draws ~70W from the outlet, unless it's a pentium M. I'd say it's probably closer to 110W, but I'm just guessing.

Yahoolian wrote:

Would a desktop work? A high efficency power supply combined with an undervolted, possibly underclocked, (mobile?) CPU might be a viable option.

yes, a desktop would work - although her office space is small so smaller is better. But power consumption is the main issue.

One problem we have is that she is not entirely certain of the specs of her solar system, and unless we know that we have to err on the low side. We know she had no problems running a laptop, and in tests with a similar laptop here we know it draw around 36 watts. This is on an old Dell PII-300. I don't know how much variation there is between that and say a current model P4 laptop or a Pentium M. We tested a 19" LCD and that draws around the same - 30-35 watts.

She doesn't need the mobility of a laptop, but she wants a 17" screen, so the main reason for looking at a low power desktop is to save money. A 17" laptop is going to come in at around $1800. My thought is if we can work out a desktop system for no more than say $1200 it would be worth the effort.

Thanks

The Shuttle SN95G5 seems to fit the bill.

http://www.silentpcreview.com/article222-page6.html

Underclock and undervolt to .8V and you'll have very low power consumption and space usage.

Yahoolian wrote:

The Shuttle SN95G5 seems to fit the bill.

http://www.silentpcreview.com/article222-page6.html

Underclock and undervolt to .8V and you'll have very low power consumption and space usage.

Page 8 has the good wattage table: 51W with Cool n Quiet, 105W under a max load, a la Folding.

Yeah, I was trying to point out the under volting potential. So yeah, even if you simply enable Cool-n-Quiet it's pretty good.

$289 Shuttle SNG95

$51 512MB Corsair

$146 Athlon64 3000+ OEM

$225 Acer 17" LCD

$52 80GB 7200rpm HD

$11 Black floppy drive

$34 AOpen CDRW/DVD

$31.5 ATI Radeon 7000 video card

$839.5

Thanks guys, this is starting to sound promising.

I'm still trying to get her to pin down approximately how much spare capacity she has (it varies from day to day and season to season)... I doubt I will get that info but she says she can tell me what her current laptop is using. That will be our starting point...

One question - is there much to be gained power-wise in using a 2.5" drive over a 3.5?

Thanks

tangel147 wrote:

...

One question - is there much to be gained power-wise in using a 2.5" drive over a 3.5?

Thanks

The Seagate Momentus is a 2.5" drive that uses 2.3w seeking, .2w in standby.

The Seagate Savvio is a 10k RPM 2.5" drive uses from 4.8w to 6.8w, though it's SAS, U320 and Fibre only.

By comparison, the Seagate Barracuda 7200.7 is a 3.5" drive that uses .7w in standby and 12.5w seeking, over 5 times more wattage than the Momentus when in use.

I decided to spec out an Aria SFF system.

Replace the Shuttle SNG95, motherboard, video card and CPU with:
$93.5 RS480M2-IL with integrated video, Cool'n'Quiet

$116.5 Antec Aria

Same price: A64 3000+ retail CPU

That comes out to $729. Pretty good eh?

A disadvantage is that there is no room for a floppy drive. A flash drive would help with that.