PSU for my system - size - is my choice correct?

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VladTepes

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Hi I posted this in the PSU thread itself but not sure if anyone will notice it there, so posting as its own thread, as I need a response.

I have read the instructional portions of the PSU sizing thread, which are very useful :)

I am building a dual system off of one PSU using a Phanteks Power Splitter.
The systems are as follows:

ROMULUS

MOBO: Asus Z170I Pro Gaming LGA 1151 Mini ITX
RAM: Corsair CMU32GX4M2C3200C16R 32GB (2x16GB) DDR4 3200MHz Vengeance Black with Red LED
CPU: Intel Core i7 6700K Quad Core LGA 1151 4GHz Unlocked CPU Processor
GPU: NVidia GeForce GTX970 FTW
SSD1: Samsung 950 Pro Series 512GB M.2 SSD (boot/system/office)
SSD2: Samsung 840Evo 500Gb (game library)
SSDD3: Might or might not use it Samsung 840Evo 256Gb
HDD1: WD Blue 6Tb
Optical: LG 16x BluRay R/W & DVD R/W (LG-BH16NS40)
Fans ???

REMUS (The NAS system)

Mobo: Supermicro X11SSL-F
CPU: Intel i3-6100
RAM: 32Gb Samsung ECC unbuffered RAM
Boot / System drive: Kingston V400 120Gb SSD
NAS drives: 4 x WD Red NAS 3TB (but cater for 5).


So this is my calculation. Where the internet indicated a number of figures for power consumption the higher figure was used. This has resulted in a very conservative outcome - probably far exceeding the actual requirement.

OK so with the specs I've posted in mind we have:
MOBO 2 x 80W = 160W (I'm sure the real figure would be much lower)
HDD's 6 x 35W = 210W (Normal load is lower, but this allows for possible simultaneous spin up of all drives).
SSDs x 4 @ 3.5W = 14W
CPU1: i7 6700K 91W TPU
CPU2: i3 6100 51W TPU
RAM 4 x DDR4 16gb @ 6W each max = 24W
GPU: 300W max (some sources 250W)
Blue Ray Drive: 30W (max while writing)

Fans - say 4 or 5 case plus 2 CPU fans - so I've said equivalent of 5 140mm fans @ 30W each (again likely to be a massive over-estimate) = 150W

There will also be an Arduino and a few LED strips running off it, they don't take up much at all.

The total PEAK consumption based on my calcs is 975W.

In reality it will be much lower most of the time, but being this is includes a NAS system I need to ensure no potential issues.

This thread says to multiply the figure by 1.25 to get a target PSU size, which works out around the 1200W mark. )

In short, the 750W supply will probably be fine. But probably doesn't really satisfy me I really want to be sure any POTENTIAL PEAK use of the two system simultaneously does not exceed the comfort / efficiency level of the power supply. Admittedly this scenario - peak use of both systems simultaneously is extremely unlikely.

So I suppose I'm on the lookout for a fully modular 1200W PSU Gold 80+ rated. Or am I?


Interestingly if we look at various power calculators on the internet they calculate the draw / recommendations as follows:
Powersupplycalculator 584W Draw, Recommend 804W
MSI calculator Recommend minimum 494W (I assume this is their estimated actual draw figure, but can't be sure)
Coolermaster calculator: 616WDraw, Recommend 716W

(For others reference, powersupplycalculator link was dated - no 6th gen CPU's etc.)
(The easiest to use was the Coolermaster one.)

Whether any are correct - well, that's a tough one.

For a typical gaming or home use system I'd use the Coolermaster calculator, with a very high degree of confidence.

For a system including NAS (in this case FreeNAS) it gets a bit more complicated and doing it manually highlights some real-world differences.

Hmmm.
smile.gif


Recommendations from other forums suggest that "750W would easily do the job", and that "850W would be plenty".

I'd appreciate advice / thoughts on this please.

If 1000W is more than enough, then I have a line on a EVGA SuperNOVA P2 1000W PSU (1+ Year old, 80% warranty left, 9.7 score from JohnGuru) for a good price but need to know ASAP.

Thank you ! :)
 

tvsjr

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You need to do a better job on your power numbers first.
Hard drives... here's the data sheet for the HGST NAS drives, which are 7200RPM. https://www.hgst.com/sites/default/files/resources/DS_NAS_spec.pdf - 30 watts maximum (watts = volts * amps, sum the 5 ans 12 volt rails)
Fans... if you have a 35-watt fan, they call that a blower, and you wouldn't want to be in the same room with it.

Re-run your numbers using the data sheets.
 

VladTepes

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I hoped that I had gone over the top stupid.
I have had some issues tracking down spec sheets but, as you've done, I suppose an HGST drive and WD drive at 7200rpm will be using very close to the same amount of power.
Thank you. :)
 

VladTepes

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ROMULUS
MOBO: Asus Z170I Pro Gaming LGA 1151 Mini ITX https://www.asus.com/Motherboards/Z170I-PRO-GAMING/ No Wattage specified
RAM: Corsair CMU32GX4M2C3200C16R 32GB (2x16GB) DDR4 3200MHz Vengeance Black with Red LED http://www.corsair.com/en/vengeance-led-32gb-2-x-16gb-ddr4-dram-3200mhz-c16-memory-kit-red-led-cmu32gx4m2c3200c16r No wattage specified
CPU: Intel Core i7 6700K Quad Core LGA 1151 4GHz Unlocked CPU Processor 91W TPU
GPU: NVidia GeForce GTX970 FTW http://www.anandtech.com/show/8568/the-geforce-gtx-970-review-feat-evga/2
“a 145W TDP card, so the use of 2 sockets provides some additional buffer room along with the card’s 110% (160W) TDP overclocking limit.”
This source http://au.evga.com/Products/Product.aspx?pn=04G-P4-2978-KR says max 170W so I’ll go with that.

SSD1: Samsung 950 Pro Series 512GB M.2 SSD (boot/system/office)
SSD2: Samsung 840Evo 500Gb (game library)
SSDD3: Might or might not use it Samsung 840Evo 256Gb
HDD1: WD Blue 6Tb see below.
Optical: LG 16x BluRay R/W & DVD R/W (LG-BH16NS40)
Fans ??? see below

REMUS (The NAS system)
Mobo: Supermicro X11SSL-F http://www.supermicro.com/products/motherboard/Xeon/C236_C232/X11SSL-F.cfm No wattage specified
CPU: Intel i3-6100 51W TPU
RAM: 32Gb Samsung ECC unbuffered RAM M391A2K43BB1-CPB
Boot / System drive: Kingston V400 120Gb SSD
NAS drives: 5 x WD Red NAS 3TB see below.


So this is my calculation.

Where I could not find data on the net I have used the figures recommended on this (FreeNAS) forum. (for example mobo and RAM)

OK so with the specs I've posted in mind we have:
MOBO 2 x 80W = 160W (I'm sure the real figure would be much lower)
HDD's 6 x 30W = 180W max
https://www.hgst.com/sites/default/files/resources/DS_NAS_spec.pdf
SSDs x 4 @ 3.5W = 14W
CPU1: i7 6700K 91W TPU
CPU2: i3 6100 51W TPU
RAM 4 x DDR4 16gb @ 12W each max = 48W
GPU: 170W
Blue Ray Drive: 30W (max while writing)
Fans - say 7 fans total, using Phantek fans as a reference. http://www.phanteks.com/PH-F140SP.html says 1.8W whereas http://www.phanteks.com/PH-F120XP.html says input 2.4W so lets call it 2W*7 = 14W total.

There will also be an Arduino and a few LED strips running off it, they don't take up much at all.
LED strips say 12V*2.4A=25W (https://learn.adafruit.com/rgb-led-strips/current-draw) assumes 2m of led 60/m strip.
Arduino 5V*46.5mA = 233mW, small enough to ignore completely ! (http://gadgetmakersblog.com/arduino-power-consumption/)

The total PEAK consumption based on my calcs is now looking more like 783W

783*1.25= 979W so I’ll buy me a EVGA SuperNOVA P2 1000W PSU http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=361

confident that'll be plenty :)

Cheers :)
 

tvsjr

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Just for reference, my Supermicro system in my sig, which is far beefier than yours and running a load of 15K drives, pulls less than 500 watts during spin-up. I think you'll be golden with the 1KW PSU. I personally prefer the Seasonic power supplies, but that's your call.
 

Stux

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rogerh

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Just for reference, my Supermicro system in my sig, which is far beefier than yours and running a load of 15K drives, pulls less than 500 watts during spin-up. I think you'll be golden with the 1KW PSU. I personally prefer the Seasonic power supplies, but that's your call.

As a matter of interest, what have you measured your spin-up power consumption with? There was a thread[1] about such measurements in this forum, and it appears you need something with sufficient bandwidth to have a rise time of less than about 10o milliseconds to get a reliable answer.

[1] https://forums.freenas.org/index.php?threads/how-to-measure-the-drive-spin-up-peak-current.38885/
 

tvsjr

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As a matter of interest, what have you measured your spin-up power consumption with? There was a thread[1] about such measurements in this forum, and it appears you need something with sufficient bandwidth to have a rise time of less than about 10o milliseconds to get a reliable answer.

[1] https://forums.freenas.org/index.php?threads/how-to-measure-the-drive-spin-up-peak-current.38885/
Supermicro has power measurement built in. That said, I would certainly not expect it to be as high-resolution as a proper external measurement.
 

rogerh

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Supermicro has power measurement built in. That said, I would certainly not expect it to be as high-resolution as a proper external measurement.
It depends how they do it. Unless they specifically mention peak spin-up power it may be more geared to slow changes.
 

VladTepes

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Thanks again.
Yep I'll be getting the evga supply for a good price and still under warranty.
This particular model, at least, is very high quality.
The seasonic PSUs are hard to get over here in Aus and expensive to import.
 

Stux

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The EVGA is a nice PSU, I went with the Corsair RMx for mine and am quite happy with it.
 
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