The Power Supply Thread

[trurl]

On 9/6/2022 at 2:17 AM, Lolight said:

The reegularly updated PSU tier list:

 

https://cultists.network/140/psu-tier-list/

Go for a single rail model

[tucansam]

Have modern SFX PS's caught up to ATX's in terms of build quality, wattage, and bomb-proof-ness?  I need to replace a decade-old ATX PS as I'm trying to solve a strange issue that might be PS related.  I have room for another ATX, but moving to an SFX would allow me quite a bit more cable management and customization, every little bit of room matters.

 

This would be a 10th gen i7 with 15 spinners and two NVMe SSDs, along with a super lower power VGA card and an LSI HBA.  Several fans, nothing major.

 

Cold start power-ons and parity checks are of course my main concern, when power draws are maxed.

 

As an aside, I am reading through this thread now, but any recommendations on a good PS in an appropriate wattage would be appreciated. 

 

Thanks.

[Lolight]

On 10/23/2022 at 9:57 PM, tucansam said:

any recommendations on a good PS in an appropriate wattage would be appreciated.

You can check the link in the prior posts above.

[Stubbs]

Is it possible for a molex connector to not deliver enough power to an HDD?

I recently upgraded my server from 3TB WD Reds to 10TB Seagate Ironwolfs, and the Ironwolfs kept returning errors in my server. Sometimes I'd get the parity sync working, but it would work at about 800kbps which would've taken about a year to finish.

I fixed it by taking the Seagates out of the Hotswap Bay and into the case's internal 3.5" bay, and connecting them directly to both the motherboard (SATA) and the PSU (SATA Power connector).

My Hotswap Bay has two SATA power connectors, and one of them is powered by a Molex connector (because that's all I could fit). Could a Molex cause a power bottleneck for higher capacity drives?

 

 

Edited November 1, 2022 by Stubbs

[Vr2Io]

15 minutes ago, Stubbs said:

Could a Molex cause a power bottleneck for higher capacity drives?

No.

 

15 minutes ago, Stubbs said:

Ironwolfs kept returning errors in my server

Problem there.

[zipityzi]

On 12/27/2021 at 9:27 AM, NAStyBox said:

I went from gold to gold. 

Old - https://www.amazon.com/Seasonic-Semi-Modular-Control-Application-SSR-550LM/dp/B08WNL4ZFJ
New - https://www.amazon.com/Corsair-RM850x-Fully-Modular-Supply/dp/B08R5JPTMZ

 

Then the UPS load went from 229 to 225. 

 

I think that's due to 80+ ratings being minimums. So PSUs even just below Platinum still are rated Gold. The Corsair RM850X actually is Platinum-level efficient at 20% load / 170W (Platinum minimum: 90%; achieved: 90.5%), but it's just a bit short for 50% load / 425W (Platinum minimum: 92%; achieved: 91%) and 100% load / 850W (Platinum minimum: 89%; achieved: 86%). 

 

For those PSUs, according to the 115V efficiency charts by SeaSonic and Corsair:

1. Seasonic SSR-550 (80+ Gold): This PSU is ~90% efficient at 250 watts.
2. Corsair RM850x (80+ Gold): This PSU is ~91.5% efficient at 250 watts. 

1.5% loss @ ~250W is 3.75 watts additional loss, which looks close to your data.

Edited December 11, 2022 by zipityzi
sig figs

[zipityzi]

On 10/23/2022 at 10:57 AM, tucansam said:

Have modern SFX PS's caught up to ATX's in terms of build quality, wattage, and bomb-proof-ness?  I need to replace a decade-old ATX PS as I'm trying to solve a strange issue that might be PS related.  I have room for another ATX, but moving to an SFX would allow me quite a bit more cable management and customization, every little bit of room matters.

 

This would be a 10th gen i7 with 15 spinners and two NVMe SSDs, along with a super lower power VGA card and an LSI HBA.  Several fans, nothing major.

 

Cold start power-ons and parity checks are of course my main concern, when power draws are maxed.

 

As an aside, I am reading through this thread now, but any recommendations on a good PS in an appropriate wattage would be appreciated. 

 

Thanks.

 

This might be too late for a reply, but to answer the general question of SFX vs ATX:

 

To paint broad strokes, SFX & ATX today can overlap on quality & watts with two exceptions: 1) ultra-short millisecond-type GPU spikes / transients beyond the rating (due to smaller capacitors on SFX models) and 2) availability of 850W+ SFX PSUs. 

 

SFX are still quite a bit pricier & rarer (e.g., availability, region), though. Still, 650W from an SFX PSU = 650W from an ATX PSU, all other things equal.  To actually compare SFX vs ATX: it'd have to be a model vs model comparison, as the overlap goes both ways: good SFX beats bad ATX, but good ATX beats bad SFX. The PSU's test results matter more than the form factor, which is an improvement from the earliest SFX days.

[Stubbs]

Is the information in the OP of this thread outdated? My understanding of PSUs was that having a higher wattage rating did not necessarily result in higher power draw, but the OP says this:

 

"2. The minimum capacity that can power your build. Any more will just waste power."

 

Isn't efficiency what matters more here? Like Bronze/Gold/Platinum/Titanium?

 

I want to buy a new Titanium PSU for my Unraid Server, and there is a good discount for one where I live, but it's rated at 850W.

My Unraid Server currently has a maximum load wattage of roughly 280 W.

[Lolight]

18 hours ago, Stubbs said:

Isn't efficiency what matters more here? Like Bronze/Gold/Platinum/Titanium?

Here's a short, nicely written overview:

https://adoredtv.com/how-to-choose-the-right-power-supply/

 

but more importantly, make sure to get a high quality, community tested model:

https://cultists.network/140/psu-tier-list/

[TheGleaner]

What would be recommended for being a redundant type and having at least 18 molex plugs and at least 1600w in an ATX or very close form factor?

 

I currently have an old zippy/emacs 2+1 redundant psu rated at 800w, but I am getting very close to that rating being pulled at startup.

 

I have found I can get what i want from zippy/emacs, but it would be special order through any distributor and they are not very interested in ordering just 1.

[spiritamokk]

Hi everyone,
 

I'm seeking some advice on a power issue I'm facing with my Unraid build, particularly involving my Seasonic Prime PX-750, a 750W 80+ Platinum PSU.
 

Background: A few months ago, I built my Unraid system with 10 x 18TB Seagate EXOS drives, and everything was running smoothly. Recently, I decided to expand my storage by adding 5 more drives, bringing the total to 15 HDDs. For power distribution, I'm using a dedicated peripheral power connector on the PSU for each set of 5 drives, connected via StarTech SATA Power Splitter Adapter Cables.
 

Issue: As soon as I connected the 5 new drives, the PSU made a single click sound, and the system failed to boot. After disconnecting and reconnecting the PSU power cable, the same issue occurred. However, when I removed the 5 new drives, the system booted successfully with the original 10 HDDs. Attempting to boot with 11 drives resulted in the same failure. Funny enough If I connect 6 drives on the same power cable, system boots, but it does not feel safe to daisy chain this many drives on the the peripheral SATA connector.
 

I've researched this PSU before buying and it was recommended for Unraid builds by many users, so I assume that it would be able to handle 15 drives. Is there something I'm missing here? Could the PSU be faulty? I still have the option to return it to Amazon.
 

System Specifications:

CPU: Intel i7 8700K

Motherboard: Asus Maximus X

RAM: 16GB DDR4 (2x8GB)

HBA: LSI 9300-16i

SSD: Samsung 980 Pro 1TB

HDDs: 10 x 18TB Seagate EXOS (trying to add 5 more)

PSU: Seasonic Prime PX-750, 750W 80+ Platinum

Case: Rosewill RSV-L4500U
 

I'd really appreciate any insights or advice on this matter. Thank you in advance!

[_cjd_]

On 1/25/2024 at 8:31 PM, spiritamokk said:

Hi everyone,
 

I'm seeking some advice on a power issue I'm facing with my Unraid build, particularly involving my Seasonic Prime PX-750, a 750W 80+ Platinum PSU.

<snip>

I'd really appreciate any insights or advice on this matter. Thank you in advance!

 

First - a word of warning: I recently lost two drives to a failing power supply - not really sure what failed, but the smell indicated something burned up. I was lucky in that they were only 500GB drives I was using to test some configuration options on a new build... It would work fine with just a single spinning drive (was fine with multiple SSD) so I can only suspect startup surge was too much. Granted, this was an older Corsair power supply so may not have had protection circuitry built in at the quality the Seasonic will; hopefully you don't encounter anything like this.

 

Troubleshooting needs to be step by step.

First, verify that all 5 of the new drives spin up as the only drive plugged in; then as sets. Can you get all 5 together? And those 5 plus another 5? This is just to confirm there isn't a bum drive in the mix.

 

Does it matter where the 10 drives are plugged in? First thing is to verify that all the ports on the power supply function; can you redistribute the 10 drives across 3 vs the two you have now (if I'm reading your configuration right)? Can you add any additional drives with the distribution changed? If you can't change where the drives are plugged in, you probably have a faulty power supply.

 

If, however, they work without regard to where they're plugged in but it starts failing to work after 11 or 12 or whatever, you're probably exceeding the output capability as the drives spin up. I would still experiment a bit to see if the number which will spin up changes depending on which drives are in use - again verifying there isn't an anomalous drive in the mix. Unfortunately, I can't find any specs on this for these HDDs, but do see a datasheet for a different variant Exos puts it at 32W startup (2.6A). That's still likely within the capabilities of this power supply+system. The fact it sometimes works / doesn't work with even 11 drives makes me think something else is happening.

 

If you have hot-swap capabilities or are brave, you could also try adding drives one at a time after the system is powered up. That will reduce the initial startup surge. I can't recommend this w/o hot-swap bays unless you're confident in what you are doing and/or are willing to lose hardware.

 

It may be worth reaching out to Seasonic regardless.

[JonathanM]

On 1/25/2024 at 9:31 PM, spiritamokk said:

For power distribution, I'm using a dedicated peripheral power connector on the PSU for each set of 5 drives, connected via StarTech SATA Power Splitter Adapter Cables.

Disconnect all drives, and test each drive power connector individually with a cheap tester like this.

[bigup]

Looks like the much loved RM550X 2021 is now EoL and not readily available anymore

 

how does the RM650X 2021 compare at low loads?

 

Whats the next best available PSU after the RM550X 2021?

[Doktor-X]

On 2/4/2024 at 10:48 AM, bigup said:

Looks like the much loved RM550X 2021 is now EoL and not readily available anymore

 

how does the RM650X 2021 compare at low loads?

 

Whats the next best available PSU after the RM550X 2021?

I dont know if you watch this video 

And this doc

https://docs.google.com/spreadsheets/u/0/d/1TnPx1h-nUKgq3MFzwl-OOIsuX_JSIurIq3JkFZVMUas/htmlview#gid=110239702

But ill buy coolermaster mwe 400 when i get chance, to replace my thermaltake Toughpower 600w from 2008 since i have problems spining down my drives with my new bkhd n100 board and this old psu. But when i try my rm850x from my main pc all works fine and i have lower power consumption, and since colermaster have similer efficiency like corsair ill buy coolermaster since price is below 50€

Edited February 11 by Doktor-X

[bigup]

52 minutes ago, Doktor-X said:

I dont know if you watch this video 

And this doc

https://docs.google.com/spreadsheets/u/0/d/1TnPx1h-nUKgq3MFzwl-OOIsuX_JSIurIq3JkFZVMUas/htmlview#gid=110239702

But ill buy coolermaster mwe 400 when i get chance, to replace my thermaltake Toughpower 600w from 2008 since i have problems spining down my drives with my new bkhd n100 board and this old psu. But when i try my rm850x from my main pc all works fine and i have lower power consumption, and since colermaster have similer efficiency like corsair ill buy coolermaster since price is below 50€

 

Great find, thanks for this, since my last post I did indeed purchase a brand new Corsair RM650x 2021 to replace my 10 year Super Flower 650w, I thought it was time for an upgrade, plus modular is most welcomed!
 

The RM650x 2021 cost me £65 and currently number 16 on the spreadsheet, I did try to find a RM550x 2021 but impossible to find in the UK.

 

comparing the 650x 2021 and 550x 2021, according to the chart:

 

At 20W efficiency thats 1.41% difference
At 40W efficiency thats 1.05% difference

 

1% in the real word being negligible?

 

compared to the SuperFlower the RM650x has dropped idle power by around 5w so im happy with this. but also kind happy the old PSU kept being this good, even after 10 years, I thought it may started being inefficient by now!

 

I am running 12 HDDs, 2 SSDs and 1 NVME

 

I think the key thing here is to get the highest efficiency PSU you can at the lowest price.

 

 

 

 

[Doktor-X]

Update, so i have recived my cooler master mwe 400 white psu, and..... well i'm not impressed by it. When you look at wolfgang's PSU list you can get impression that mwe 400 is as good as now discontinued corsair rm550x. But i'm experiencing different results. To be fair when i replaced my aging thermaltake toughpower 600w psu from 2008 i did manage to lower power consumption of my BKHD N100 board by like 10w. From 50 to like 40w when all my drives are spinning. But at idle i'm like i say NOT impressed. When all disks are spindown and all case fans disconnected, and only unraid usb and only my cache ssd running (that contain my dockers), with mwe i'm pulling 24W from wall, but when i tested my corsair rm850x from my main pc i manage to pull 18W from wall. (fan on corsair did not run on that low load but i dont think that this is main reason why corsair have lower power consumption)
But also i must say that with my old thermaltake toughpower 600w psu from 2008 and with this board, i did have problems spinning down first drive in my array. So this was main reason why i needed new psu. Strange that this old psu works just fine in my old unraid setup just fine, all drives was able to be power down, maybe reason is that this thermaltake is atx 2.2 standard and maybe this new boards need newer standard like 2.52.

All and all, the story goes, i'm pulling right now 30w from the wall with 3 case fans, all disks spindown and only one ssd working which is cache and dockers drive and cpu is only in C3 but this is do to jmb585 controller.

Edited February 27 by Doktor-X

[darkside40]

Just ordered the MWE 400 by myself.

Till now i have a Super-Flower SF450P14XE but that is already 13 years old, so it might be a good idea to have a replacement at hand.

 

To be honest if it pulls 5W more out of the wall than a Corsair RM550x i dont mind. I bought it now for 60€ which is approx. half of the price of the Corsair, if you can even buy it anywhere.

 

Prices for PSU's have gone mad in the last couple of years.

[darkside40]

Okay the MWE400 need approx. 2W more than my old Superflower.

So i will let it sit on the shelf till needed.