PicoPSU 120W sufficient for server use?

elg2001 · Post by **elg2001** » Tue Jun 05, 2007 9:20 pm

Hi,
I'm a LONG time SPCR reader, although my post count probably doesn't reflect that

I'm looking to build a quiet server to replace the Infrant ReadyNAS NV+ I just sent back. What a piece of crap. But that's beside the point. I just want a fast file server that can encode 1080p video every once in awhile. Here are the components I plan on using:

- Core 2 Duo @ 2.13 GHz
- Intel-branded G33 chipset motherboard
- TWO 1 GB sticks of RAM
- FOUR 500GB Samsung hard drives to be run in RAID5
- Integrated Intel gigabit ethernet

Do you guys think there's any chance that a PicoPSU could power this system? The G33 chipset has integrated video which I will use sparingly considering it will be sitting in the corner most of the time.

I'm very open to undervolting options if you guys know of any. I need to use the above components, and I'd like to get away with a PicoPSU if possible.

theyangster · Post by **theyangster** » Tue Jun 05, 2007 10:23 pm

you might, but I'd be worried about the HD draw on the 12v line, since the MB and CPU will most likely take most of 12v line, I could be wrong on this

wouldn't hurt to try

tehfire · Post by **tehfire** » Tue Jun 05, 2007 10:49 pm

I think that's pushing it...it would probably be fine at idle, but seeing that the TDP of the Core 2 alone is 65W...I just doubt it.

johno · Post by **johno** » Tue Jun 05, 2007 10:53 pm

It'd have to be in there with a chance. The Intel chipset is fairly heavy on power at idle, but with C2D doesn't peak very high under load. I'd estimate the idle usage at the power supply output at 9W per hard disk plus 35W for the rest - making about 70W. Then C2D idle/full load differential is 20 to 30W, giving a peak around 100W out of the supply. I think hard disk start-up current is fairly well contained these days, so shouldn't represent too much of a surge.

If you don't really need zero downtime on single hard disk failure, you could get a bit more headroom by going back to 3 disks and RAID-0.

Bluefront · Post by **Bluefront** » Wed Jun 06, 2007 3:17 am

I'd guess it would probably work ok as long as the 12V power supply was at least 120W. You could always step up to the 200W model converter and use something like I am....a 180W power supply from Radio Shack. From what I gather, all these PICOs just pass the 12V line into the system, meaning a 3.5" drive is running directly off the 12V input, not the PICO.

klankymen · Post by **klankymen** » Wed Jun 06, 2007 6:23 am

FWIW, I was playing around with a power meter recently, measuring all my stuff. anyways, since I have external hard drive, I can easily measure hard drive power draw.

figures are as follow:
-startup: 35W
-idle: 10W
-seek: 12W.

This a an USB enclosure with a 500GB Samsung HD501LJ inside of it, which is a fairly cool and quiet (therefore maybe low power draw??) hard drive.

Anyways, probably a few watts are lost in conversion, but I dont think it's too much. I don't have the meter right now, but I could for maximum accuracy test by hotswapping with the internal sata connectors, since I can account for the efficiency of my NeoHE.

elg2001 · Post by **elg2001** » Wed Jun 06, 2007 10:36 am

Well there's always the 200-watt picopsu option as well, but I can't find any external bricks that can output 200 watts without a fan.

Can anyone help?

Also, does anyone know of any good G33 boards with good undervolting options both for ram and cpu?

Bluefront · Post by **Bluefront** » Wed Jun 06, 2007 1:23 pm

The 180W 13.7V power supply from Radio Shack works very well.....but it has a fan. However, the fan only turns on if the thing ever gets too hot. I've never heard the fan in either unit I have, even running in the summer. The 120W Pico will not start much over 13.8v.....the 200W version will start with higher voltage. So check the actual voltage of the power supply before you buy it. Some of these things have an internal voltage adjustment, The RS unit does not.

SixedUp · Post by **SixedUp** » Wed Jun 06, 2007 2:01 pm

I was wondering if the 120w PicoPSU could cope with 2xSamsung 501LJ's, a laptop drive, and a C7 mini-ITX motherboard. All of a sudden my plans look rather tame in comparison

Cheers
Richard

elg2001 · Post by **elg2001** » Tue Jun 12, 2007 11:39 pm

anyone know of power bricks about 200 watts that do not use a fan?

charonme · Post by **charonme** » Thu Jun 14, 2007 7:55 am

i'm looking for a powerful 12V ac/dc for the PW-200-V too

jaganath · Post by **jaganath** » Thu Jun 14, 2007 7:56 am

can you get one of these in your country?

chinna_n · Post by **chinna_n** » Thu Jun 14, 2007 11:11 am

klankymen wrote:FWIW, I was playing around with a power meter recently, measuring all my stuff. anyways, since I have external hard drive, I can easily measure hard drive power draw.

figures are as follow:
-startup: 35W
-idle: 10W
-seek: 12W.

This a an USB enclosure with a 500GB Samsung HD501LJ inside of it, which is a fairly cool and quiet (therefore maybe low power draw??) hard drive.

Anyways, probably a few watts are lost in conversion, but I dont think it's too much. I don't have the meter right now, but I could for maximum accuracy test by hotswapping with the internal sata connectors, since I can account for the efficiency of my NeoHE.

I agree. I happend to measure current for 320GB and 200GB HDDs( seagate/Maxtor) and both were in the above range. Maxtor being 3-5watts less during startup.

So, pico psu with 120watts, noway it can startup that setup. May be you can buy those HDD powersupplies $6/each with shipping from ebay, and standard 120watts to go with it to power system alone.

Or you could use PW-200 200watts DC-DC supply, may be with this gateway 180 watts brick probably made by delta

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0128254174

smilingcrow · Post by **smilingcrow** » Fri Jun 15, 2007 12:24 pm

It might just power it under load but startup may very well be problematic. Kinda ironic!
I measured a Core 2 Duo 2GHz as consuming 111W A/C under load (dual Prime95) and that was using a P965 chipset and a NVidia 7300GS 256MB.
Assuming power supply efficiency of 80% that translates to a DC load of ~89W. You can deduct ~5W when using an IGP which gives you a figure of 84W. This was with one 400GB Samsung and 2GB RAM. Deducting the 84W from the Picoâ€™s 120W gives you a spare 36W for your three drives which is achievable.

The Pico I believe is rated for a constant load of 120W but may well be able to safely deliver a peak load of more than that for the brief time needed for your drives to startup. According to the SPCR review itâ€™s rated for a Peak combined load of 140W.
If not, you can always buy two of them and share the load; theyâ€™re certainly small enough.

That also makes it easier to source silent power bricks as itâ€™s easier to find two silent 80W models than one silent 120W+ model.

Note that you want to find a motherboard that doesnâ€™t slightly over-volt as that can add 10W to the system consumption. The figures I gave above were obtained by undervolting using RMClock and werenâ€™t particularly aggressive settings.

If you want to lower the power consumption I suggest using a 945G based chipset board but youâ€™ll lose the native RAID 5 support, so unless youâ€™re using a RAID card this obviously isnâ€™t a solution for you. Data here: viewtopic.php?t=33420&highlight=