08-06-2019, 03:34 AM
Hi, I am also using an ATX power supply in my home NAS (4 HDDs, 2 fans and the RockPro64).
I can tell you, the 80+ marking (unless you think of an expensive 80+ Titanium model) on the PSU is of no use to you here. That is because that denotes the peak efficiency of the PSU under a specified load (between 20% and 100%. See the Wikipedia article describing the requirements for the certification.
Now, your (and mine) problem is that HDDs have their rotating disks that need enormous power on startup (my 4 HDDs draw ~80-90w on spinup), but once their disks are on speed, their power usage drops quite dramatically (4 HDDs and the RockPro use about 20-25w max. together after the disks are spun up).
That is why you would easily need the 600w PSU for the startup of your NAS, but after your disks are running, you can do with a lot less.
In my case, with an older 240w PSU, once the disks are spun up and the HDDs + RockPro64 only use about 20-25w (The PSU is below 10% load here!), the efficiency drops to about 50% and I measure 40w power use at the wall plug. Unless you have an 80+ Titanium PSU (Which do cost several 100€), the efficiency of your PSU is not even definen below 10% load. Newer PSUs should be able to stay above 75% efficiency, but do not expect to stay above 80% with only HDDs and a RockPro64 attached. Unless you buy an expensive 80+ Titanium rated PSU.
Currently, I have measured the 60w PSU that Pine64 sells with the RockPro64 already to be more efficient in my system than my older 240w ATX PSU. With today's switching power supplies, almost any PSU that you can operate at 75-80% of its rated power will be more efficient than the standard ATX PSU.
So, if you really want to hold your power usage down by using an efficient PSU, rather get a smaller one and connect a larger, more powerful PSU as a 'booster' on startup. Since you want to run 24/7, it is a manageable task as you would be doing it just once (you can reboot / powercycle the RockPro64 with its buttons without ever having to turn off the disks again). Of course you need to be more careful with this procedure...
Greetings,
Matyas
I can tell you, the 80+ marking (unless you think of an expensive 80+ Titanium model) on the PSU is of no use to you here. That is because that denotes the peak efficiency of the PSU under a specified load (between 20% and 100%. See the Wikipedia article describing the requirements for the certification.
Now, your (and mine) problem is that HDDs have their rotating disks that need enormous power on startup (my 4 HDDs draw ~80-90w on spinup), but once their disks are on speed, their power usage drops quite dramatically (4 HDDs and the RockPro use about 20-25w max. together after the disks are spun up).
That is why you would easily need the 600w PSU for the startup of your NAS, but after your disks are running, you can do with a lot less.
In my case, with an older 240w PSU, once the disks are spun up and the HDDs + RockPro64 only use about 20-25w (The PSU is below 10% load here!), the efficiency drops to about 50% and I measure 40w power use at the wall plug. Unless you have an 80+ Titanium PSU (Which do cost several 100€), the efficiency of your PSU is not even definen below 10% load. Newer PSUs should be able to stay above 75% efficiency, but do not expect to stay above 80% with only HDDs and a RockPro64 attached. Unless you buy an expensive 80+ Titanium rated PSU.
Currently, I have measured the 60w PSU that Pine64 sells with the RockPro64 already to be more efficient in my system than my older 240w ATX PSU. With today's switching power supplies, almost any PSU that you can operate at 75-80% of its rated power will be more efficient than the standard ATX PSU.
So, if you really want to hold your power usage down by using an efficient PSU, rather get a smaller one and connect a larger, more powerful PSU as a 'booster' on startup. Since you want to run 24/7, it is a manageable task as you would be doing it just once (you can reboot / powercycle the RockPro64 with its buttons without ever having to turn off the disks again). Of course you need to be more careful with this procedure...
Greetings,
Matyas
(08-01-2019, 08:32 AM)ZeblodS Wrote: @stuartiannaylor: Just to answer a few of your talking points.
I was thinking of using a regular ATX power supply for several reasons, the main one is that it's cheaper to get 12V and 5V at pretty high amperage.
For instance I can find an brand new EVGA 600W with a single 12V49A rail and a 5V20A rail for less than 50€. More than enough to power safely the ROCKPro64 and 10 to 12 hard-drives.
Plus it's rated 80+, meaning less electricity wasted. And usually brand names power supply don't destroy all your hardware when they fail (which all power supply end up doing eventually, even brand names one as I have already experienced it after 7 years 24/7 powered on).
It has 6 SATA power connector, that can be doubled using adapters like these.
Power supply, for machines running 24/7, is really not something you can really spare expenses on.
I looked over for a USB3.0 solution, using a PCI-E like the one you linked. UASP adapter with 12V input for 3.5" harddrives are not that cheap either, I have found models like this one for instance. Plus I'd need a few USB3.0 hub to connect 2 to 3 UASP adapters per USB ports on the controller, with maybe 5V external connection to not overpower the PCI-E controller with that much disks.
In the end it won't be cheaper than the IOCrest SI-PEX40097 SATA controller, and it's a less clean solution, but it's a fallback solution for sure.
For the casing, I'd still go the individual hot-swap from the front route as it's way more practical IRL, even if it cost more. The Orico one can be found for 8.75€ a pop when bought by 10 or more.
Software wise, I'd need to do some more research into it, and some testing before going toward a different solution than what I already use. But on first glance Snapraid seem to have many advantages indeed.
EDIT: the USB solution could be cheaper using something like these:
https://m.fr.aliexpress.com/item/32897789991.html
https://m.fr.aliexpress.com/item/32829472708.html