SOLVED Need help finding the right PSU for build

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Scorm

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So let's get to it, here's my build so far :
  • Motherboard
  • CPU
Intel Xeon E3-1260L

TDP: 45W, Idle: ~10W
~ 45W
  • RAM
4 x 8GB DDR3L 1600MHz ECC Unbuffered (Treated as 1.5V RAM for calculations, as noted by Supermicro)

~24W = 4 x 6W
  • HDD
6 x 4TB Seagate Ironwolf [ST4000VN008]

Avg: 4.8W, Idle: 3.95W, Sleep: 0.5W, Startup current : 1.8A
Should take no more than 4.8 + 1.8*12 => 27W per drive
162W = 6 x 27W
  • Cooling
3 x 120mm fans

~67.5W = 3 x 22.5W
  • PSU
EDITs :

(1)
With these estimations (based on jgreco's thread "Proper Power Supply Sizing Guidance"), I have a peak consumption of 324W, and idle of 150W.
He also suggested to multiply the peak Watts by 1.25 for the target power supply size.
So I'm looking at a PSU from SeaSonic close to 405W.

If you have some more reliable values for estimates, I'll be glad to use them.
Also, I don't care about the modularity.

(2)
I went for a Seasonic G-450.
 
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Stux

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Stux

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Scorm

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Or skip all of that and just jump to the preaculated guesses for the lazy geek

https://forums.freenas.org/index.php?threads/proper-power-supply-sizing-guidance.38811/

I wanted to invest the time to do it right. But it's difficult to find good power consumption information on hardware.
I did use that thread without the precalculations because it would be too rough.
I also feel like I fall just in between the 360W and 450W PSUs.

No. Online drive calculators tend not to take hd startup currents into account.

By omitting the HDD part of the calculator and adding my calculated values, I get 305W peak.
 
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Stux

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I wanted to invest the time to do it right. But it's difficult to find good power consumption information on hardware.
I did use that thread without the precalculations because it would be too rough.
I also feel like I fall just in between the 360W and 450W PSUs.



By omitting the HDD part of the calculator and adding my calculated values, I get 305W peak.

Yeah, I wanted to do it right too...

See here: #7

For a very similar post to yours ;)

Difference is, the lazy recommendations stop before you get to 24 bays :)

In the end I went with a 1000W PSU.

Now, when I built my 6 drive Xeon D system (very low power), I just went for a 550W. I would've been able to easily get away with 450W, but the RMx range only goes down to 550W.

If I were you, i'd go with at least a 450W, like the lazy recommendations say for your E3 class system ;)

Actually, i'd go with the Corsair RM550x anyway, because I like it :)

Another thing to consider is larger PSUs come with more SATA connectors.

At the end of the day, sum it all up except the HDs, add the peak HD spin up current, multiply by a lot, and you end up with what the lazy recommendations recommend.
 
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Pezo

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Another thing to consider is that with modern power supplies you don't really lose much if the PSU is oversized.
Looking at the specs for 80 Plus, efficiency is pretty much the same between 20% and 80% load.
I personally would go with a bigger PSU just so that you have some headroom for adding drives in the future. Stux' 550W seem reasonable.
 

Ericloewe

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I'm a fan of the Corsair RMx PSUs for FreeNAS builds.
I haven't confirmed Corsair's prices, but Seasonic's Focus line is eating everyone's lunch. Crazy performance on par with the X-series while undercutting everyone else's prices.
 

Scorm

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Seasonic G-450 it is. Thanks for the help... thread is now "solved". :)
 

Inxsible

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