PSU Died- What to replace with?

[Suse User]

The Hiper Type-R PSU in my 2nd UnRaid has died and I'm looking for a replacement.

 

I currently have 10 HDDs in there but would like the replacement PSU to be able to cope with the 16 Capacity limit with 1 120mm fan per 4 HDDs in a 4into3 adaptor caddy (fan total 5 x 120mm fans + PSU HS-Fan).

 

I'm using a Coolermaster Stacker that allows for 2 PSUs but I've always preferred to use a single PSU for ease of cabling and airflow.  I've had a look around and noticed that a number of PSUs quote "Single 12v Rail".  Is this a good thing for Unraid usage?

 

Machine has Celeron 3.2Ghz, 1 Gb Ram, Modest Gfx and needs to take 16 HDDs.

 

I'm looking for energy efficiency in a replacement PSU, hopefully modular to keep any unnecessary connectors out of there.  Anyone have any suggestions?  or Opinions on the 1PSU vs. 2 PSU choices?

 

Thanks,

 

Mark.

[guitarlp]

Tom builds his servers with the PC Power and Cooling 610w PSU. I bought the 750w just to be safe. The 750 watt PSU has a 60A 12v rail which is more then enough to power 15 hard drives. If you search on this board you'll find many people say they're one of the best.

 

The only downside is they're not modular... so you'll need to spend some time organizing/hiding all the extra cables.

[Suse User]

Looks like a good PSU,  I'll certainly consider it.

 

I'm trying to work out whether single rail or multiple rail is the better option for Unraid.  I think I may go for a CorsairTX750 (Also non modular but long cables) at £77 ($153) Delivered if single rail is the better option.

 

I have the lower powered TX620 Modular in my other unraid with 15HDD non problem but the 750 has more power and higher efficiency for the same money as the 620 if I can give up the modular feature.

 

Thanks,

 

Mark.

[NAS]

I seriously think you will regret not getting a modular PSU. The day i purchased my first one is the day I vowed not to go back..

 

OK so i may be exaggerating but NAS boxes have enough cables as it is without adding some you don't use.

 

Go modular (said in a cheer leading chant).

[SSD]

Everyone has their personal preferences.

 

I'd recommend 120mm fans.  The 80mm fans tend to be noisier and don't cool as well.

 

For "green" purposes, you want to look at the efficiency ratings.

 

I'd recommend at least 600w to run 16 disks.  Personally, I'd go for a 750w (if I were buying a new one today) to have room to grow to 20-25 disks.

 

If you are using 5400 RPM "green" drives from WD, their power draw is considerably smaller, so a smaller PSU would be requried.

 

If you are using lots of disks, chances are you will be using most of the modular drive connectors.  Modular vs non-modular would be little more than a tie breaker for me.  Hiding a couple of PCI-E power connectors isn't such a big deal.

 

I will pay a premium for good MBs, fast CPUs, fast memory, and even a well designed case - but I tend to be cheap with PSUs.  I run my unRAID box with 15 drives (2 green) with a 550 watt "Mad Dog" (old CompUSA brand).  It works great for me needs.  ~$50 on sale 1.5+ years ago.  Watt draw goes to about 575 at bootup, but quickly goes back to about 200s (~80 with everything spun down).

[bubbaQ]

Single rail is invariably better... but single rail for a 650 Watt PSU means around 50 amps of current on that 12V rail, which exceeds some safety standards.... hence the proliferation of "dual rails" and the PSUs that (in the US) are advertised as "dual rail" but in fact, are single rail when you open them up.

[WeeboTech]

I find it interesting how power supplies are sometimes over sized for the application.

Is 750W really needed for a 15 drive NAS array?

 

When using the corsair calculator, it comes out to 520/550...

http://www.corsairmicro.com/psufinder/default.aspx

 

So is the extra wattage needed for headroom?

 

One of the points I found interesting about the 520 was the following

Triple 12V Rails provide independent reliable power to the CPU, video card and other components with a combined rating of 50A (40A on 520W) maximum! Advanced circuitry design that automatically enables power sharing between the triple +12V rails in an event of overload on any single +12V rail.

 

I think I may just go for this one as even from my calculations on drive wattage use, it's within reason.

 

[Suse User]

I find it interesting how power supplies are sometimes over sized for the application.

Is 750W really needed for a 15 drive NAS array?

 

When using the corsair calculator, it comes out to 520/550...

http://www.corsairmicro.com/psufinder/default.aspx

 

So is the extra wattage needed for headroom?

 

One of the points I found interesting about the 520 was the following

Triple 12V Rails provide independent reliable power to the CPU, video card and other components with a combined rating of 50A (40A on 520W) maximum! Advanced circuitry design that automatically enables power sharing between the triple +12V rails in an event of overload on any single +12V rail.

 

I think I may just go for this one as even from my calculations on drive wattage use, it's within reason.

 

 

I didn't know about that calculator.  From what I gather it's the simultaneous startup of 15 HDDs that draws extra power momentarily, but I have the 620W modular version of the Corsair in my 15 HDD other unraid and that's been working fine.

 

I thought I'd go for the 750W as it has extra efficiency, the 620W claims "up to 80% efficiency" but doesn't meet the performance fof the newer versions and is the same price.  I'm assuming the power draw will be similar but more surge headroom?

 

Mark.

[SSD]

I find it interesting how power supplies are sometimes over sized for the application.

Is 750W really needed for a 15 drive NAS array?

 

I was basing my statements on the fact that my 15 drive system is pulling ~575 watts today (according to my UPS).  I said 600w for 16 drives and 750w with room to grow to 20-24 drives.

[Suse User]

Hmm TX650 May be the price/performance sweetspot here 

 

http://www.corsair.com/products/tx.aspx

 

I just bought one for £53.08 ($105.28USD) Delivered.

[WeeboTech]

I was basing my statements on...

 

I realize, however, if you add up the actual hard drive power usage of 24 drives you still may not need 750 Watts.

Now if you had a very hot SLI arrangement and a heavily over clocked quad core with all sorts of peripherals. Maybe you'll need the extra Juice.

 

By setting your drives to "power up in standby" you will reduce the startup surge.

 

My statement is based on observations that power supplies are being made to put out so much more power.

People choose supplies add a lil extra headroom... Business looks at the demographics of sales... Makes higher power ones..

People buy larger supplies (bragging rights??). (no offense meant to anyone).

 

I think it's wiser to do the math with actual usage of parts and choose a supply within that range.

 

In response...

but I tend to be cheap with PSUs.  I run my unRAID box with 15 drives (2 green) with a 550 watt "Mad Dog" (old CompUSA brand).{/quote]

 

In the long run it might be cheaper to spend on a quality power supply which runs with high efficiency and shows that a 600W will do fine in an efficiently designed unRAID machine.  It's the single rail that really matters.

 

Nothing's personal here.. just some interesting observations regarding power supply choices and the trend these days.

[jimwhite]

Another thing to consider is that efficiency ratings are highest at some particular percentage load.... i.e. using a 750 watt PSU at 500 watt load may be less efficient than a 600 watt PSU at 500 watt load.... the reviews at silent pc talk about these things...