Question PSU Questions

daniel_542

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Hi there everyone!

So, current system specs as follows:
A88M-G/3.1 Motherboard
AMD A10-7700K
Corsair H55 120mm dual fan (push/pull config) AIO
2x16GB DDR3 (running 1066)
256GB SK Hynix NVME (Boot)
256GB SK Hynix SATA SSD (Games)
5 1TB HDDs } 4 of these are 7200RPM
1 2TB HDD } 2 of these are 5400RPM
DVDRW drive
R9-280X 3GB XFX GPU
7 Case fans - all 80mm with LEDs in them but not RGB

I am looking for a suitable power supply but this is proving difficult as I can't seem to get an accurate estimation of the wattage needed for each rail. I get one result from one PSU calculator (outervision one) and differing results from things like corsair or other PSU manufacturer's calculators.

Can anyone give me an idea of what I will need as outervision says I need 131W combined on the 3.3v & 5v rails and almost 500w on 12v rail - recommending a 650W PSU but there isn't a 650W psu that kicks out that amount on the 3.3v & 5v rails - best I can find is a 750W with either 120 or 130W on 3.3/5v combined.

Anyone out there able to give me a better breakdown of what wattage the PC will take from experience please?
My current PSU is struggling as it is aged - voltages intermittently going out of spec causing system freezes and shutdowns or failure to start up at all in some cases.
I am on a tight budget so any advice on the right PSU is more than welcome.
Cheers people!!!
 

AntonyLovric

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EVGA 650W (one recommended by outervision for these specs) has 120W on the 3.3 + 5v rails. (it's also a little more expensive.) That should be adequate. It's funny the 750 model has the same 3.3/5 capacity (probably uses the same parts between the 650 and 750).

You probably need that much because of the @ of drives in the system. (Have you thought about replacing some of the 1TBs with a single 4TB? It will reduce your power requirements and thermals) I changed the calculator from 6 drives to 2 and the wattage on the 5v and 3,3 dropped 11 watts.

https://pcpartpicker.com/product/BtrYcf/evga-b5-650-w-80-bronze-certified-fully-modular-atx-power-supply-220-b5-0650-v1

There are other models (seasonic 650W Focus Plus Gold) that have 125 W on the 3.3 and 5v rails.
 

daniel_542

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EVGA 650W (one recommended by outervision for these specs) has 120W on the 3.3 + 5v rails. (it's also a little more expensive.) That should be adequate. It's funny the 750 model has the same 3.3/5 capacity (probably uses the same parts between the 650 and 750).

You probably need that much because of the @ of drives in the system. (Have you thought about replacing some of the 1TBs with a single 4TB? It will reduce your power requirements and thermals) I changed the calculator from 6 drives to 2 and the wattage on the 5v and 3,3 dropped 11 watts.

https://pcpartpicker.com/product/BtrYcf/evga-b5-650-w-80-bronze-certified-fully-modular-atx-power-supply-220-b5-0650-v1

There are other models (seasonic 650W Focus Plus Gold) that have 125 W on the 3.3 and 5v rails.
Thank you for the suggestion of changing hard drives but I don't have the kind of cash for that right now. Plus, it uses storage spaces parity on all drives. My intention is to slowly replace each drive with a bigger one but keep the parity running across all drives (I am even tempted to add a 7th drive in as this would give me room for 2 simultaneous drive failures.

The outervision calculator says I will be 131W combined 3.3 & 5V rails so the 120W of the EVGA one wont be enough according to that and I don't want the same thing happening to the new one as is happening with this one due to out of spec voltages. I have a 750W in there now (Powercool 850 80+ White) but the voltages intermittently drop well out of spec (12V Rails - GPU and main motherboard - go down to 11.2V, 5V Rail drops to 4.3V and 3.3V rail drops to less than 3V. System freezes or BSODs and then struggles to restart afterwards unless I disconnect all the wires and reconnect them inside the PC and even then, it takes ages to initialise past POST). Current PSU over 5 years old between me and its previous owner so I guess it is just on the way out. Was considering a TX750M as that does 130W 3.3 & 5 V combined which is as close as I can get without going up to an 800/850W PSU which then takes it past my price range if I want one that has a decent brand name and reviews to it. Hence posting on here for advice.

So all in all, unless I am misunderstanding the "Combined" marker on most PSUs for the 3.3 & 5V rails, I need to find one that kicks out 130W combined between them as per the following info that outervision psu calculator has provided me (taken directly from the outervision site):
My usage:
Load Wattage:590 W
Recommended UPS rating:1100 VA
Recommended PSU Wattage:640 W

Amperage (combined)
+3.3V​
+5V​
+12V​
11.7 A​
18.6 A​
42.3 A​
132 W​
508 W​

3.3V Rail - 11.7A - 38.61W
5V Rail - 18.6A - 93W
Total 3.3 & 5V rails - 131.61W

12V Rail - 42.3A - 507.6W

Total on all rails - 639.21W

Based on the total, a 650W would be fine but not a single 650W I have found gives out anywhere near 130W combined 3.3 & 5V (most are 100-105W at best), best I have found that does is the TX750M or other known brands at 750W level.
PS. I round off the couple of extra watts as it will only be max power for a few seconds at startup while all the hard disks spin up and the DVD drive starts up, once things are running, I doubt I will ever hit that maximum unless storage spaces keeps all drives spinning all the time.
 

AntonyLovric

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Unfortunately it looks like most PSUs under 1000 watts have @ 120 - 125W on those two rails. If you're concerned about startup / inrush you might be able to set certain drives to 'delay' their power up. (Most BIOS'es used to be able to delay the start of a drive by up to two or three seconds.)

DVD startup would be minimal if there is no disk.
 

daniel_542

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Unfortunately it looks like most PSUs under 1000 watts have @ 120 - 125W on those two rails. If you're concerned about startup / inrush you might be able to set certain drives to 'delay' their power up. (Most BIOS'es used to be able to delay the start of a drive by up to two or three seconds.)

DVD startup would be minimal if there is no disk.
Unfortunately, my BIOS doesn't support delayed startup for hard disks or other devices (I am on latest version) so that isn't an option for me.
I have found a few that have 130W combined 3.3 & 5V rail at 750W and 850W so I think I will have to stick to one of those (TX750M and a few others do this and there is a Goldefield GPG 850 modular which says it kicks out 150W on 3.3 & 5V rails. Are Goldenfield PSU's any good or should I avoid?
 

NightHawkRMX

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Outervison vastly over estimates power consumption. It is quite misleading. I wouldn't worry about power on minor rails, its not going to be used much at all. Your GPU and CPU are going to use almost exclusively 12v, and that's where the real power consumption is.

For reference, I ran an i5 760 (95w) + R9 280x (250w) on a fairly old but still decent quality Corsair CS450M 80+ Gold and it worked perfectly without a single hiccup. Your system likely will have similar power draw. Wattage per rail on the CS450M is below.


Even though you can use a lower wattage PSU, I would reccomend a high quality ~550w for your computer, just to leave some wiggle room and room for upgrades.

What is your budget and what country do you live in?

Out of curiosity, what PSU do you currently have?
 

daniel_542

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Outervison vastly over estimates power consumption. It is quite misleading. I wouldn't worry about power on minor rails, its not going to be used much at all. Your GPU and CPU are going to use almost exclusively 12v, and that's where the real power consumption is.

For reference, I ran an i5 760 (95w) + R9 280x (250w) on a fairly old but still decent quality Corsair CS450M 80+ Gold and it worked perfectly without a single hiccup. Your system likely will have similar power draw. Wattage per rail on the CS450M is below.


Even though you can use a lower wattage PSU, I would reccomend a high quality ~550w for your computer, just to leave some wiggle room and room for upgrades.

What is your budget and what country do you live in?

For reference, what PSU do you currently have?
My concern is that most PSU calculators are estimating 600-650W due to the number of hard disks I have in there , if I remove them, it drops it out to around 500ish so I get your point there but with 6 mechanical hard drives, the DVD drive and the fans installed, it uses more than a 450/550 would kick out either way...

My 12V usage is showing 550-620W no matter what calculator I use (it varies depending which calc I use) but the outervision one is the only one I can customise with all devices including the USB devices I have connected a lot of the time (that are not self powered).
This is why I I aiming higher than 650W PSU. I am hoping someone can let me know regarding the GPG one I have spotted as it is well above and beyond what I need but I can't find any decent reviews on it.

Goldenfield GPG 850 80+ Gold Fully Modular PSU

Please can someone let me know if this would be a safe option?
Specs say it has OVP/UVP/OCP/OPP/SCP/OTP protections and Temperature control built in so I suspect it wont be a bad one - anyone had any experience with this PSU at all?
 

NightHawkRMX

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I don't know much about that unit aside from seeing it on Amazon and I believe I saw one reviewer build a PC using a bunch of goldenfield products including that PSU. I wouldn't reccomend it unless you can find a reputable review of the unit.

While it claims to have those protections it would take a proper test to see if they actually work and are set correctly. It isn't uncommon for PSUs with XYZ protection to actually not have that protection functioning properly. EVGA Supernova G3 comes to mind.

You aren't going to be utilizing (writing to or reading from) all of those hard drives at the same time, I would bet. I still think you are over estimating your power consumption, especially on those minor rails.
 

Karadjgne

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Corsair RMx650 is 130W combined, 25A per rail.

But that's not the issue. The problem is that ypu have no idea exactly how much power your hdds can pull. Look at the labels. A hdd can generally pull anywhere from 15 to 30w, some maybe more or less. Calculators just guess.
 
Goldenfield GPG 850 80+ Gold Fully Modular PSU
This is a new PSU that came out in 2020 (based 80 plus data). I heard Golden Field is capable of making good PSUs, but like @NightHawkRMX said, better find ones that have a good review. Also, it only has 103 W combined on the minor rails, so I don't know where you got that 150 W from.

Like I said you are overly worrying. If I were you I'll just pick up a decent Corsair PSU like the CX 650 (with 25 A each for 3.3 V and 5 V with 130 W combined) and call it a day.

On top of that you have the fact that the triggering points of the protection that shuts the PSU down in the minor rails are often set much higher than what it is rated at. Around 130-150% the rated capacity to be exact. That means you can have more spare room at your disposal, without shutting down.
 
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