Most efficient PSU, slightly odd spec system..

blueacid

blueacid

blueacid

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So I'm dusting some old hardware off to build a file server for my home, but would like an efficient power supply to go with. Noise isn't an issue.

So the spec:
Intel P2 @ 350Mhz, 512MB ram, wired NIC, PCI SATA adaptor (not hardware RAID)
Four 2TB Green SATA drives.

...I think I'll be needing around 100watts; would I be far wrong with that guess? What'd you recommend for this? Looking at the FSP120-50GNF as with a fan fitted that ought to be fine.
Equally, what about a 120+watt PicoPSU; would one of those swing this kind of load 24/7 comfortably? Or would that be a bit too optimistic?

Cheers,
Blueacid
 
According to wiki that CPU needs about 20w. Not sure how much an old mainboard would use. PSU wattages used to be very small back in those days.

The green drives use around 6 watts each and the nic needs around 6w too. Ram needs about 3 watts per stick. A fan will draw 3 watts or less.

So 20 + 24 + 6 + 3 + 3 + mainboard.

I reckon a pico-psu driven by a 100w 12v power brick would be fine but I might be tempted to go a touch higher for comforts sake as it's so hard to estimate power draw accurately. The 12v bricks are very efficient too. As for which one to get? No idea? FSP are good in this sector though I believe.
 
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Tealc said:
According to wiki that CPU needs about 20w. Not sure how much an old mainboard would use. PSU wattages used to be very small back in those days.

The green drives use around 6 watts each and the nic needs around 6w too. Ram needs about 3 watts per stick. A fan will draw 3 watts or less.

So 20 + 24 + 6 + 3 + 3 + mainboard.

I reckon a pico-psu driven by a 100w 12v power brick would be fine but I might be tempted to go a touch higher for comforts sake as it's so hard to estimate power draw accurately. The 12v bricks are very efficient too. As for which one to get? No idea? FSP are good in this sector though I believe.
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Nice, by the sounds of it a Pico PSU maybe up to the job.

In fact I think I still have a P3 rig somewhere that runs from a home-made DC-DC PSU that I made for car use, older hardware does seem to be pretty easy to power it seems...
 
Hmm one consideration is that the pico PSU should be able to convert a fair amount of it's current to 5v as a lot of the old components used 5v rather than today's more popular 12v.

I'm not into pico PSUs so don't know much about their capabilities.
 
I'll grab my electricity monitor back from a mate and see how much it's using.
I'm also going to email a couple of suppliers of Pico PSUs (in that OCUK don't seem to sell them) to see if they can advise me further as well.

Let's suppose that there's no suitable Pico PSU; what would you guys advise otherwise? What's the most efficient low wattage ATX PSU?
 
Like modern PSUs the Pico-PSUs seem to favour the 12v rail for the amount of power it can provide. The 5v and 3.3v rails on just about everyone I've looked at provide about 6A to each rail. 5Ax6v = 30 Watts, 5Ax3.3v = 16.5 Watts. Now whether the P2 took a mixture of voltage to power itself from the mainboard or just one of the rails I just don't know.

SPCR might be a good place to research the sort of thing you need.
 
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There don't seem to be many 80 Plus Gold PSUs available in low wattage. I believe it's quite hard for manufacturers to achieve the 20% load value.

I'm using an FSP Aurum 700W which is also available in 400W. This is a 90% efficient PSU. I modded mine by swapping the fan though as it's stock fan is a tad fast for my liking. Difficult to find these babies though. Either they are very popular and have sold out or they are only on limited distribution at the moment.
 
blueacid said:
I'll grab my electricity monitor back from a mate and see how much it's using.
I'm also going to email a couple of suppliers of Pico PSUs (in that OCUK don't seem to sell them) to see if they can advise me further as well.

Let's suppose that there's no suitable Pico PSU; what would you guys advise otherwise? What's the most efficient low wattage ATX PSU?
Click to expand...

The Nexus value 430W or FSP Green PS FSP400-60GLN 400W PSU will be overkill in terms of output power, but it's efficient and quiet, and reasonably priced.

It's a shame more manufacturers don't give more detailed efficiency ratings though, but some review sites like SPCR actually test PSU's properly so your best bet would be to head over there and check out the PSU reviews.

Here's the efficiency of the Nexus:
screenshot.20-04-2011%2000.23.25.png

Source: http://www.silentpcreview.com/article922-page5.html

It looks pretty good, around 80% at 100W, bear in mind this was test at US mains voltage, but I imagine the results will be pretty similar at 230v. :)
 
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