[SOLVED] Help me understand 5V rail and setup 3.5 HDD home storage

[Current96a]

Hello All. My interest in this topic is mainly PSU, but there is also some HDD info and topics.

I hope my question makes sense and helps other people who decide to make their own storage server, box, cloud at home.

• I have a general home use PC that basically nobody uses. It is basically a non brand name office PC that once I used for gaming and work.
• It has office grade 400w PSU from LC power: 3.3V = 21A ,5V = 15A , 12V1 = 11A , 12V2 = 14A
• From what I understand, devices such are HDD and SSD, use mainly 5v and 12v rail.
• I plan to put 8 to 10 3.5HDD's in that PC so that I could use it as a main storage for my work, and mby even try HDD "mining"
• I plan to use 3tb Hitachi HDD's that can be found cheap on used market in my area + I already have 2 for a year now without any problems.
• On data sheet and specification, those HDD's work on 11-12W, 5V - 1.2A max , 12V - 2A max
• On internet I have read how those HDD's may go up to 20W also.

So I basically wonder if 15A on 5V and 14A on 12V2 rails are enough for 10 HDD's such are these? If yes, how many more could I attach hypothetically???

I wonder this because:

• If HDD were to use 20W max, on 5V rail that gets to 4A and on 12V - 1.66A - 10 HDD = 200W, 5V 40A , 12V 16.66A
• If HDD were to use 12W max, on 5V rail that gets to 2.4A and 12V - 1A - 10HDD = 120W, 5V 24A , 12V 10A
• If HDD were to use 5V 1.2A max = 6W and 12V 2A max = 24W - 10HDD = 5V 12A 120W , 12V 20A 240W

Am I missing something? Am I that bad at electronics math? 😀

PS. Please dont point me in directions how I may need some better PSU because LC power is off brand. It's not off brand,. Its 15+ year EU brand which focus on market of continental EU, not US, and it works just fine. According to asus mobo's volt monitor's, it even gets more precise 5v and 12v than my workstation's cooler master that could be found on tier 2 or B or whatever on ur "psu list".

 

[thx1138v2]

Your 5V rail supports a max load of 15A. Ten drives * 1.2 amps = 12 amps so that will work with 3 amps overhead. Other devices in the system will probably use some of that 3 amp overhead.

Your 12V1 rail supports a max load of 11A. Ten drives * 2 amps = 20 amps which will overload that rail. So 5 drives * 2 amps = 10 amps which is under 11 amps but close to limiting out. Don't know what else you plan on that rail.

Your 12V2 rail supports a max load of 14A. Five drives * 2 amps = 10 amps leaving 4 amps on that rail for other devices.

Or you might want to put 4 drives on the 12V1 rail and 6 drives on the 12V2 rail to balance them a bit better.

 

[SkyNetRising]

Look for PSU, that has enough connectors for all your sata drives.
If it doesn't have them, you'll have to deal with huge mess of daisy chained adapters. That leads to spotty power delivery - random hdd disconnect issues are common.

Your current PSU is not 400W. It's less than 300W (11 * 12 + 14 * 12=300).
HDDs mainly use 12V.
For 10x HDDs required wattage would be 10 * 12 * 2=240W (on 12V rail).
Then you need to account also required power for cpu, motherboard, ram, gpu.

It depends on rest of your system, but currently - if you connect 10 HDDs to it, you will blow up your PSU
(and probably kill something else in the process too - some/all hdds and probably motherboard too).

 

[USAFRet]

for 10 HDD's

What will these 10 HDD's be doing?

In addition to the above, the startup power draw of spinning all these drives up at the same time is substantial.

A better solution might be an external enclosure or two.
8 bay MediaSonic or similar. Connect via eSATA or USB 3.

 

[--SID--]

• office grade 400w PSU from LC power: 3.3V = 21A ,5V = 15A , 12V1 = 11A , 12V2 = 14A

LC-Power Office series is garbage, one of most garbage psu's you can buy in EU.

it even gets more precise 5v and 12v

Have you measured ripple output?
With 10 HDD there is a very unbalanced load on a groupregulated psu. 5V will be very low near 4,7v and 12v very high near 12,6v.
Actually this psu doe not have two proper 12v rails. 12v is usefull when each rail has it's own OCP but LC-Power Office series don't have OCP at all. I think one of the fake rails (12V1) is for EPS, The second fake rail is connected to ATX, SATA and Molex.

 

[Current96a]

Good points guys. Ty for fast responses.

I plan to use 8 to 10 HDDS for personal storage. I need storage space for my videography work, and I expect to need it even more. Along the way, I want to try "HDD mining" in all this crypto craze. I can get decent used HDD's or so I feel, thus I plan to try something like this.

This PC will have:

I3 3240
8gb ddr3 ram, 16 if it gets needed
1 or 2 PCI to SATA risers
PCI to M2 for SSD (system).
2-3 Case fans if it gets needed - 12cm

This alone to me seems to fit fine on 12V1 11A from mentioned PSU, but with not much room for more.

But 10 HDD's on other rail... I will definitely need PSU with larger capacity. So can you help me out understand what specifications am I gonna need to run this machine? I will definitely look for stuff that has good protection standards and certifications. OVP, OPP and OCP seem to me as a must here, due to protection of HDD's. Any other protections that I should take as a must have?

Your 5V rail supports a max load of 15A. Ten drives * 1.2 amps = 12 amps so that will work with 3 amps overhead. Other devices in the system will probably use some of that 3 amp overhead.

Only 3 amps overhead on 5V sounds low. To be safe I feel like I need to get something with 18-20A on 5v. Would something like that be necessary, or do I need to go for bit more?

As for 12V rail... It seems to me that I should be aiming for something with at least 35A on 12V if single. If with dual 12V rail, then I guess that I will need at least 24-26A on one rail, right?

By now I think that I should have put: "Help me understand PSU spec's needed to setup 3.5 HDD home storage", in title. 😀

 

[USAFRet]

I plan to use 8 to 10 HDDS for personal storage. I need storage space for my videography work, and I expect to need it even more. Along the way, I want to try "HDD mining" in all this crypto craze. I can get decent used HDD's or so I feel, thus I plan to try something like this.

Seriously consider a prebuilt NAS box.
Instead of having ALL of these internally in your system.

I have 12 drives in or attached to my QNAP.
Currently, 51TB available space.

Easily upgradable space.
I'm about to replace some of the older 2-3TB drives with 16TB.

 

[Current96a]

Seriously consider a prebuilt NAS box.
Instead of having ALL of these internally in your system.

I have 12 drives in or attached to my QNAP.
Currently, 51TB available space.

Easily upgradable space.
I'm about to replace some of the older 2-3TB drives with 16TB.

Well I did, and I would. But at start of it all, it just is cost effective to me to use my current system and add some cheap drives to it, or it seems to be. I have 2 answers for you why I wouldn't use NAS for start of this all.

1. I would not go less than 4 hdd slots. So I have options for new QNAP and Thecus in 300-400$ spectrum. Mby even 50$ more. I am not sure about used market tho. So let's say I get 4 slot Thecus for 300$. Drives that I could mostly get my hands on are 3TB. That means 12TB total, with cost of 160-180$ for 4 drives (40-45$ each). So I spend 460-480$ total for 4 HDD max. I know it is more efficient but like that I get less memory for cost + I feel that I will need that memory pretty soon, leaving me with no room to try mining out.

2. If I spend 400$ on 10 HDD wtih 3TB in them, that leaves the other 60-80$ for PSU and mby bit above for ergonomics and Im good to go. With that, for same money, I get close to 3 time more memory, which leaves room for both mining and work usage. In the end, all 10 hdd's will fit fine in my case - almost like an nas box 😀


I definitely wont need more memory than 30tb for my work in a long time for now. But for time being I wont even need half of that, which I will use to test out HDD mining. STORJ, SIA, BTT, BURST. If I see demand for more memory, I will probably go for NAS from there on.

 

[USAFRet]

Well, do you want good and stable, or do you want cheap and fragile?

Looks like you're after the latter.

 

[USAFRet]

"HDD mining"
Storj?

I looked into that a while ago.
Laughable.

I absolutely would not subject my systems and LAN to that. Not a chance.

 

[Current96a]

Well, do you want good and stable, or do you want cheap and fragile?

Looks like you're after the latter.

It's experimental and fun. Goes with my primitive slavic tradition 😀

We are going out of topic for no reason. I was asking for support over PSU specification when HDD's are in question.

 

[DSzymborski]

Too bad you can't power hard drives with hostility, because you've got a lot of amps on that rail.

 

[Current96a]

Too bad you can't power hard drives with hostility, because you've got a lot of amps on that rail.

At least you have a better sense of humor, than the rest of your buddies.


I opened a PSU-STORAGE related topic here, in aim to get and share more info on PSU and its connection to internal storage devices. Other people tomorrow will come to this topic for that info and to share their experience.

I ask about PSU spec's needed to run 10 HDD's INSIDE a PC.

Your MODERATOR, asks "What will these 10 HDD's be doing? ". Why do you even care what they will be doing?
Only to continue to suggest what MIGHT be better.

What will these 10 HDD's be doing?

In addition to the above, the startup power draw of spinning all these drives up at the same time is substantial.

A better solution might be an external enclosure or two.
8 bay MediaSonic or similar. Connect via eSATA or USB 3.

I may have ignored him in my first response up there, because I really didnt care for NAS drive, and I really wanned to focus only on PSU for start. Besides, If I had money and possibility for NAS drive, if I wanted NAS drive, I would not be here opening this topic.......But right after my first response after opening this topic, he continued to recommend NAS drive and casualy added how he is having a good time with his NAS drive. Why? No one asked for him having 51tb free space on nas drive...

Seriously consider a prebuilt NAS box.
Instead of having ALL of these internally in your system.

I have 12 drives in or attached to my QNAP.
Currently, 51TB available space.

Easily upgradable space.
I'm about to replace some of the older 2-3TB drives with 16TB.

Ether way, I had respectfully answered him and pointed out why I cant go with NAS drive at the moment. How I did think about that, but decided to leave it for future builds if it get's needed. I did answer fully and plainly and totally respectful : "I know it is more efficient but like that I get less memory for cost "
And also, I did answer to him what I am gonna do with those 10 HDD's.


What did I get from answering to him? Why of course - undermining and disrespect :

Well, do you want good and stable, or do you want cheap and fragile?

Looks like you're after the latter.

"HDD mining"
Storj?

I looked into that a while ago.
Laughable.

I absolutely would not subject my systems and LAN to that. Not a chance.

Fragile?

Laughable?

HOW AM I NOT INSULTED?!?!?

Hostility well deserved, and you know it.

 

[USAFRet]

Why do you even care what they will be doing?

I asked what they would be doing, because the what often has major impacts on the how.

Good luck, Sir.

 

[4745454b]

Why do you even care what they will be doing? Only to continue to suggest what MIGHT be better.

Something that happens VERY often here is someone posts "how do i do x?", and they never considered y. Or even know about it. Any time anyone starts talking about running 10 hdds it makes me twitch because that's another 10 points of failure.

I get what you are saying about reusing your parts and from a cost stand point it makes sense. Your current psu will not do the job. As mentioned once above, when you power up all drives will pull thier max. Modern psus 5v railstop at 25A. Most are 20A. I don't recall seeing psus with 30A or more in a long time. This doesn't matter if it's a 450W or a 750w or even a 1500w. To do 10 or more drives you really need to split them between two psus, find another way to power them, external, or other.

If you even need to do this is something you've already shown matters to you, do I'll refrain from mentioning. But if others are telling you to not bother you might want to reconsider.

 

[SkyNetRising]

To do 10 or more drives you really need to split them between two psus, find another way to power them, external, or other.

Seasonic S12II-620 can handle 10x 3.5"drives just fine. It has 8 sata power connectors.
Then you have to use one additional molex to 2 sata power adapter.

No need for 2 PSUs.

 

[4745454b]

There is no way i would suggest someone run 10 drives on a group regulated psu with few protections. I'm glad it works for you and you are happy with it, but when i suggest a product i want to be 99.999% sure it will work and work well. I'll suggest that psu if it's the best of the bunch. But not in this case.

Looking at that psu it has 24A on the 5v rail. Yes, you have double the needed power. But you are asking for trouble using a group regulated design with a large 5v draw.

 

[vov4ik_il]

The hdd spool is what takes the most. Most 3.5 drives use 12v to power the motor. 2A per drive seems to be sketchy at peak. 10 hdd spool at the same time is 10x peak current. The PSU max values are marginal for the intended setup, as the 12v is used for other system components too. After the initial spool the current will significantly decrease so it might work.
Not recommended.
P.S You would have to disable sleep states to prevent it from spooling up and down every time and it will imply increased power draw.

 

[Current96a]

Thanks to some people on this topic, I have concluded even on my first response up on top, that I will NEED to get new and better PSU to make all this work. Now I know it can be done. It's a machine. It ether works or it needs certain circumstances do work. Or it's broken.

But the reason why I'm still here is because I still don't quite get the grasp of PSU specification needed in order to run at least 6 HDD's like mentioned, but in best scenario 10.

What i concluded till now is that 20-22A on 5V rail is a must have. But I do wonder if I should seek more?

What I concluded till now is that 35A on 12V rail should be enough to run that PC that has:

• I3 3240
• 8gb ddr3 ram
• 1 or 2 PCI to SATA risers
• PCI to M2 for SSD (OS).
• 2-3 Case fans if it gets needed - 12cm

+ 10 HDD Hitachi HUA723030ALA640 , which all run at max 5V-1.2A and 12V-2A, according to manufacturer listed specifications.
I might even be able to put WD green series, which should be bit lower power consumer, but i'm not sure if I will manage to get hand's on them.

According to internet, I got understanding that HDD's such are this Hitachi, can have 20 to 25W max load, peak power consumption. Which gave me impression how I might need 4-5A per HDD on 5V rail + 2A per HDD on 12V rail, in order to be safe. But on this topic I got impression how 4A on 5V rail might be bit unpractical and unrealistic, thus I expect to stick to info given by manufacturer - max 5V-1.2A and 12V-2A.

What are your conclusion?

I understand that many of you just decline this as UNSAFE. But keep in mind that this is experimental idea, of which I wish to know more of. And if it burns old PC or some old HDD's, so be it. But I personally doubt that something serious as that could happen if a PSU has good protection standards and certifications, along with technical and capacity spec's that could power through. Besides, when you type "burst coin hdd mining" or some similar term, you may find

Looking at that psu it has 24A on the 5v rail. Yes, you have double the needed power. But you are asking for trouble using a group regulated design with a large 5v draw.

Here you mentioned "group regulated design"which was unknown term to me up till 5-10 mins ago. If I understand right, that's a term for PSU's that have more than one 12V rail? I will research more on the matter ofc. But franky, I personally am "fan" of PSU's that only have single 12V rails. I personally, would rather have PSU with single 12V rail and strong current capacity on it, than multi rails with lower capacity that make's me scratch head bit more if it gets needed... I don't really know very much of the details, but single rail basically sound's simpler and better option if followed with good protection standards and certifications.

Now speaking of protection. I have also concluded that PSU with OCP, OVP and OPP protections is a must for this scenario. Any other protections that I should know of and seek out?

Ty for all your inputs. I'm glad that this topic got back to it's course.

 

[sonofjesse]

I have good luck with the HXI they have 25A on that rail.

https://www.techpowerup.com/review/corsair-hx750i/2.html

I think with a new power supply with enough SATA connections you will be able to do it.

Just be sure to have some good cheap 120mm fans for airflow in that case.

10HDD in a case will get warm!!

Good luck sir!

 

[4745454b]

5V * 1.2A = 6W. 12V + 2A = 24W. Combined, max draw would be 30W.

Honestly 24W on the 12V rail is nothing. There are video cards that suck down 300W easy. Cpus will use 125W. Overclocked they can hit 200ish. So 24W for a drive isn't much. The issue is that 1.2A on the 5v rail. 10 drives is 12A. Most psus top out at 25A. I found one that claimed to have 30A, but it's from an unknown company. 25A is really the best you can hope for.

"group regulated design"which was unknown term to me up till 5-10 mins ago. If I understand right, that's a term for PSU's that have more than one 12V rail?

Incorrect. It refers to the secondary side is the psu. The primary side takes the ac electricity from your wall, and converts it to the dc electricity your pc needs. The secondary side them converts that dc electricity to the voltages the pc is expecting. Group regulation has them all tied together. What happens is large draws on one rail will cause the others to change. So loading the 12V rail to 99% will make the 3.3 and 5v rail go out of spec on the low end. (Meaning the 5V rail will be less than 4.75V.) Loading the 5V rail will cause the 12V rail to be less than 11.4V. This is why i would never load a group reg psu like you are planning. Sub voltage might not sound bad but you will kill parts running them with an out of spec voltage.

if it burns old PC or some old HDD's, so be it.

Psus when they die can do more than kill a part. While not common, they can catch fire. And house fires are no fun. Again, as i mentioned above, if I'm going to suggest a part it's going to be a part that i know WILL work. I'm not going to waste your money or risk a fire/death of a part. A 25A 5v psu should be fine. But not a group reg psu.

Finally, if like to point out that your told other people in this thread you are doubt this and leave you alone, while you don't know what a group reg psu is, of what protections you should have. I REALLY STRONGLY suggest that you do a lot more reading about this. And next time someone comes in and says something is a bad idea you listen to them. Asking for links or better explanations to understand the point trying to be made is a much better idea.

 

[--SID--]

Here you mentioned "group regulated design"which was unknown term to me up till 5-10 mins ago.

I told you 10 hours before.

With 10 HDD there is a very unbalanced load on a groupregulated psu. 5V will be very low near 4,7v and 12v very high near 12,6v.

Group regulated means that 5v and 12v is regulated by the same spool. If there is an unbalanced load both 5v and 12v can't meet ATX specification

 

[Current96a]

I told you 10 ours before.

Group regulated means that 5v and 12v is regulated by the same spool. If there is an unbalanced load both 5v and 12v can't meet ATX specification

Sry. I basically forgot, with all that happened here afterwards. And probably because I didnt understand it well at first.

5V * 1.2A = 6W. 12V + 2A = 24W. Combined, max draw would be 30W.

Honestly 24W on the 12V rail is nothing. There are video cards that suck down 300W easy. Cpus will use 125W. Overclocked they can hit 200ish. So 24W for a drive isn't much. The issue is that 1.2A on the 5v rail. 10 drives is 12A. Most psus top out at 25A. I found one that claimed to have 30A, but it's from an unknown company. 25A is really the best you can hope for.



Incorrect. It refers to the secondary side is the psu. The primary side takes the ac electricity from your wall, and converts it to the dc electricity your pc needs. The secondary side them converts that dc electricity to the voltages the pc is expecting. Group regulation has them all tied together. What happens is large draws on one rail will cause the others to change. So loading the 12V rail to 99% will make the 3.3 and 5v rail go out of spec on the low end. (Meaning the 5V rail will be less than 4.75V.) Loading the 5V rail will cause the 12V rail to be less than 11.4V. This is why i would never load a group reg psu like you are planning. Sub voltage might not sound bad but you will kill parts running them with an out of spec voltage.



Psus when they die can do more than kill a part. While not common, they can catch fire. And house fires are no fun. Again, as i mentioned above, if I'm going to suggest a part it's going to be a part that i know WILL work. I'm not going to waste your money or risk a fire/death of a part. A 25A 5v psu should be fine. But not a group reg psu.

Finally, if like to point out that your told other people in this thread you are doubt this and leave you alone, while you don't know what a group reg psu is, of what protections you should have. I REALLY STRONGLY suggest that you do a lot more reading about this. And next time someone comes in and says something is a bad idea you listen to them. Asking for links or better explanations to understand the point trying to be made is a much better idea.

First moderator in this topic that said something useful. Ty for helping better understanding of group regulation design, making it easier to also understand some stuff I picked up over the interned a few hours ago.

I basically asked yesterday for how much overhead do I want on 5V rail, expecting that 20A would be enough. But it had to go 10 topics, before telling be to focus on 25A. I asked for PSU specifications that would help my situation. Later on I would easily find and pick the part that is required. I want to know what is needed. Why is it needed. SO that I can understand how it works and affects the parts of my interest. It would be much easier to just point me to some 200$ corsair, which probably doesn't even exist on my market. So I need specifications, in order to understand it all better and find what could be found. Now that I know that I need to go for 25A 5V, and independent regulation design, i have some grounds on which I will base my search for PSU of my needs.


What about protection standards?

OVP, OPP and OCP seem to me as a must here, due to protection of HDD's. Any other protections that I should take as a must have?