Which Power Supply for Unraid?

[Roscoe62]

I have a CM Stacker case, but it's the newer kind with only room for ONE P/S only. Assuming a fully stocked Unraid server, with fairly large HDD's (500Gb or more) what recommendations does everyone have for a GOOD solid reliable dependable power supply? I think I have an Enermax 550W at the moment, but see they now go MUCH larger. I've seen a Coolermaster 1000W one which looks very nice - compliant to ATX v2.2 specs with a MTBF of 100,000 hours!!!

 

Just interested in anyone's recommendations. I guess I don't have to say that reliable operation is vital.

[mikester]

Seasonic S12 600w.  It's expensive, but well worth it.  Tom's hardware did a torture test of power supplies a couple of years ago, and the Seasonics were one of only a few that survived without seriously malfunctioning (some of the cheaper ones even went up in smoke when they put them under heavy load).

[WeeboTech]

I have a few seasonic's.

From the day I put them in, there was a difference in heat and in power consumption. (and noise slightly).

The power consumption difference is under 10 watts difference per supply, but with a few machines running 24x7, it does add up.

The heat difference was noticable.(prior supplys were antec)

Stability is fine with my 3.2ghz dual xeon server and it's 8 disks.

 

If you grab a new supply, make sure it has Active PFC which makes thepower supply more efficient.

 

My question is, do you really need 1,000 watts for a machine?

 

I had a dual PIII machine running 8 disks (4x10,000rpm scsi), (4x7200rpm ide) and it used a 350w power supply without issue.

 

So.. With a server containing a modest CPU and video card, do you really need such high wattage?

I've been considering a moible CPU (2.0ghz dothan) for an unraid server.

 

 

 

 

[Roscoe62]

No, I don't need 1000watts, and the reality is - I'm unlikely to need 1000watts in the foreseeable future. What I do need is reliability and it sounds like the Seasonics are good contenders for that. I will do some research on them.

 

Thanks!

[parsec]

not trying to hijack a thread here but:

Looking at a Maxtor Diamondmax 10, Pata133, 300gig. It reads 5V 470mA and 12V 1520mA. Mind races back to 8 grade electronics class and says amps*volt=watt: (5*0,47) +(12*1,52)=slightly over 20watts. Is that correct ?

 

If yes, how come people are talking about the need for 1000w powersupplys ?. Is newer SATA drives that much more powerhungry or is it fans and motherboards that take up the juice.

/Rene

 

 

[Billped]

not trying to hijack a thread here but:

Looking at a Maxtor Diamondmax 10, Pata133, 300gig. It reads 5V 470mA and 12V 1520mA. Mind races back to 8 grade electronics class and says amps*volt=watt: (5*0,47) +(12*1,52)=slightly over 20watts. Is that correct ?

 

If yes, how come people are talking about the need for 1000w powersupplys ?. Is newer SATA drives that much more powerhungry or is it fans and motherboards that take up the juice.

/Rene

 

 

 

Eight grade math didn't include a handy formula for assessing surge requirements.  While the drive may need 20w sustained, it could be double that at power on.  Also, a "1000W" power supply offers juice that goes unused (we use primarily the 12V) and never really puts out that much power at real-world temperatures anyway.  The CPU can also take up to 100W (or more if you want with an old hot Intel).

 

All in all, a dozen drive unit can EASILY require 400W continuous and 600W when first booted up.

 

Additionally, a power supply run frequently at its limit is more prone to failure than one running at a lower percentage of its capabilities.

 

MaximumPC did a writeup on component power requirements a while back.  I bet that's the one copy I didn't keep ....

 

 

Bill