Discussion Power supply / PSU models - What to buy, what to avoid - And PSU discussion thread

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adysmajich

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Oct 29, 2018
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The Corsair AX850 is the most silent but its a bit expensive , you can get an RMi850 or an RMx 850 that would be cheaper and also silent
I have opportunity to buy AX 850i for 120 EUR (brand new) How about Seasonic Focus GX or EVGA G3? Or any other PSU?
 

Mezoxin

Upstanding
Nov 3, 2019
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its the best of the list , it should be compared to Seasonic Prime Platinum or EVGA SuperNOVA 850 T2

but for my prefrence i would still chose the AX860i for its digital monitoring and control features
 
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Aeacus

Glorious
Ambassador
Can anyone recommend me which PSU to buy?

My rig is
i5 8600k OC @4.8 Ghz,
GTX 1080 OC to 2076Mhz
DDR4 2X8 GB @3000Mhz
SSD m.2 + HDD

I was thinking of Seasonic Focus GX 750 W or Corsair AX 850 /CM series maybe? or EVGA G3?

Which of these is best option for me. I'm looking for a silent PSU, as much as possible.
For your PC, good quality 600W range PSU is more than enough, even with CPU and GPU OC. That being said, i suggest getting any Seasonic unit, in 600W range. E.g: Focus 650 (80+ Gold), Focus+ 650 (80+ Gold), PRIME Ultra 650 (80+ Platinum) or PRIME Ultra 650 (80+ Titanium),
pcpp: https://pcpartpicker.com/products/compare/WrNypg,qn7v6h,7fndnQ,fnjJ7P/

Warranty wise:
Focus: 7 years
Focus+: 10 years
PRIME: 12 years (includes all PRIME models: regular, Fanless, AirTouch, SnowSilent, Ultra)

All 3 of my PCs: Skylake, Haswell and AMD are also powered by Seasonic. Full specs with pics in my sig.

Also, PRIME Ultra 650 (80+ Titanium) is the best 650W PSU money can buy at current date and with it, you'll get the highest efficiency (92%), tightest voltage regulation (0.28%), longest hold-up time (30ms), lowest ripple noise (14mV) and longest warranty (12 years) there is. Fully modular cables and toggle-able Premium Hybrid fan control too.
specs: https://seasonic.com/prime-ultra-titanium
review: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=536


Why 650W and not 750W or 850W?
Well, let's run some numbers. GTX 1080 is 180W GPU, add the rest of the system to it at about 200W and total is around 380W.
Now, let's consider CPU and GPU OC as well since those add more wattage. Max what i5-8600K can pull @ 5 Ghz is 143.91W (source) but let's round it up to 150W for good measure. Max what OC'd GTX 1080 pulls during GPU stress test is 224W (source) but let's round it up to 250W to give some headroom.
Now, running the numbers again, we get: 150W from CPU, 250W from GPU and about 150W* from the rest of the system, making total power consumption 550W, where 650W PSU is more than enough.

* The rest of the system actually consumes less but i prefer to overestimate wattage consumption, just to be safe.
 

adysmajich

Prominent
Oct 29, 2018
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For your PC, good quality 600W range PSU is more than enough, even with CPU and GPU OC. That being said, i suggest getting any Seasonic unit, in 600W range. E.g: Focus 650 (80+ Gold), Focus+ 650 (80+ Gold), PRIME Ultra 650 (80+ Platinum) or PRIME Ultra 650 (80+ Titanium),
pcpp: https://pcpartpicker.com/products/compare/WrNypg,qn7v6h,7fndnQ,fnjJ7P/

Warranty wise:
Focus: 7 years
Focus+: 10 years
PRIME: 12 years (includes all PRIME models: regular, Fanless, AirTouch, SnowSilent, Ultra)

All 3 of my PCs: Skylake, Haswell and AMD are also powered by Seasonic. Full specs with pics in my sig.

Also, PRIME Ultra 650 (80+ Titanium) is the best 650W PSU money can buy at current date and with it, you'll get the highest efficiency (92%), tightest voltage regulation (0.28%), longest hold-up time (30ms), lowest ripple noise (14mV) and longest warranty (12 years) there is. Fully modular cables and toggle-able Premium Hybrid fan control too.
specs: https://seasonic.com/prime-ultra-titanium
review: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=536


Why 650W and not 750W or 850W?
Well, let's run some numbers. GTX 1080 is 180W GPU, add the rest of the system to it at about 200W and total is around 380W.
Now, let's consider CPU and GPU OC as well since those add more wattage. Max what i5-8600K can pull @ 5 Ghz is 143.91W (source) but let's round it up to 150W for good measure. Max what OC'd GTX 1080 pulls during GPU stress test is 224W (source) but let's round it up to 250W to give some headroom.
Now, running the numbers again, we get: 150W from CPU, 250W from GPU and about 150W* from the rest of the system, making total power consumption 550W, where 650W PSU is more than enough.

* The rest of the system actually consumes less but i prefer to overestimate wattage consumption, just to be safe.
The reason for this powerful PSU is because of the price...
I found Corsair HXi HX850i Platinum for under 140 EUR. What do you think of this model ?
 

Mezoxin

Upstanding
Nov 3, 2019
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For your PC, good quality 600W range PSU is more than enough, even with CPU and GPU OC. That being said, i suggest getting any Seasonic unit, in 600W range. E.g: Focus 650 (80+ Gold), Focus+ 650 (80+ Gold),
he has found a new corsair AXi 860w for only 120 euros so i think its a good inverstment
 

Aeacus

Glorious
Ambassador
The reason for this powerful PSU is because of the price...
I found Corsair HXi HX850i Platinum for under 140 EUR. What do you think of this model ?
HX850i is good quality and it will do fine, though it's a bit overkill wattage wise.
Here's the review of same series but 750W unit,
link: http://www.jonnyguru.com/blog/2014/08/25/corsair-hx750i-750w-power-supply/

he has found a new corsair AXi 860w for only 120 euros so i think its a good inverstment
AX860i at €20 cheaper than HX850i may seem like a better buy but do you know that Corsair AX760i and AX860i PSUs are discontinued at current date?
If you search Corsair page, you won't see those two units listed as PSUs Corsair currently offers,
link: https://www.corsair.com/eu/en/Categories/Products/Power-Supply-Units/c/Cor_Products_PowerSupply_Units

Surely there must be a good reason why Corsair discontinued those seemingly great PSUs. Perhaps due to the fundamental flaw in the design? Here's one possible reason for that,
link: https://www.legitreviews.com/intel-x99-motherboard-goes-up-in-smoke-for-reasons-unknown_150008
Hint: read the "Update 9/13/2014" for the main issue.
 

adysmajich

Prominent
Oct 29, 2018
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Thank you all guys. I know these PSU are overkills for my rig, it's just these prices are so tempting.
This AX860i is out of stock right now, and now, HX850i is on the table.
 

Mezoxin

Upstanding
Nov 3, 2019
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HX850i is good quality and it will do fine, though it's a bit overkill wattage wise.
Here's the review of same series but 750W unit,
link: http://www.jonnyguru.com/blog/2014/08/25/corsair-hx750i-750w-power-supply/


AX860i at €20 cheaper than HX850i may seem like a better buy but do you know that Corsair AX760i and AX860i PSUs are discontinued at current date?
If you search Corsair page, you won't see those two units listed as PSUs Corsair currently offers,
link: https://www.corsair.com/eu/en/Categories/Products/Power-Supply-Units/c/Cor_Products_PowerSupply_Units

Surely there must be a good reason why Corsair discontinued those seemingly great PSUs. Perhaps due to the fundamental flaw in the design? Here's one possible reason for that,
link: https://www.legitreviews.com/intel-x99-motherboard-goes-up-in-smoke-for-reasons-unknown_150008
Hint: read the "Update 9/13/2014" for the main issue.
I think they are discontinued because of how expensive they were for 700-800 w PSU , currently the only AXi version that corsair sells now is the 1600w
but i read the article and failed to see a design flaw mentioned in the PSU
 
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Mezoxin

Upstanding
Nov 3, 2019
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Thank you all guys. I know these PSU are overkills for my rig, it's just these prices are so tempting.
This AX860i is out of stock right now, and now, HX850i is on the table.
Its a great PSU , but i am not familiar with the prices of other options available for you
 

Aeacus

Glorious
Ambassador
I think they are discontinued because of how expensive they were for 700-800 w PSU , currently the only AXi version that corsair sells now is the 1600w
but i read the article and failed to see a design flaw mentioned in the PSU
Here's the issue:
Corsair along with ASUS tested the pair of AX860i power supply that Legit Reviews was using on the test bench at the time of failure on Friday the 12th. Both power supplies passed the initial Chroma test passes, but we learned something that we previously did not know. When the Corsair AXi series of power supplies came out in 2012 they featured a single rail design. Corsair switched to a multiple rail design for the power supply series in 2013 (previously unknown to us). This is obviously a significant difference in the design of the power supply. We also learned that the earlier single rail power supplies did not have OCP enabled by default.
Also, the retail price of PSU has little to do of PSU ending up as discontinued IF the PSU is very solid and don't have issues, like the no OCP for AXi. E.g Seasonic PRIME series, 80+ Titanium units start at €195, which is far more than same wattage Corsair units, yet, Seasonic still produces and sells their PSUs,
pcpp: https://fr.pcpartpicker.com/products/power-supply/#m=71&e=6&sort=price&page=1
 

Mezoxin

Upstanding
Nov 3, 2019
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Here's the issue:
I think there is a misconception here and correct me if i am wrong as i always want to learn more

I think the author of the topic was confused when he said this PSU doesnt have OCP , The PSU has the ability to switch from Single to multirail , and what this does is that it puts an OCP on each rail , Corsair didnt change the design of the PSU , all they did was make the PSU on multi rail mode on default , because OCP is moslty needed when installing a new system as there are chances of having some resistive loads such as pinched wires or broken sata connecters that cant trigger the SCP , So it made sense for corsair to alter the default setting for the PSU , but this is not a fundemental design flaw

All single rail PSU's above 500w have meaningless OCP , as their OCP is set at the maximum PSU ability , so something like a 1000w single rail PSU has its OCP at 83 AMPS , which is useless if a resistive load forms at the 12V or 3V or 5V cables , as alot of damage would allready have happened before the OCP is tripped

So OCP by design is meaningless in single rail it and it doesnt protect the equipment
 

Agraf273

Commendable
Aug 6, 2017
31
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Hello, anyone tested the bulk B9 series PSUs from BeQuite? 300w, 350w or 400w *. I am interested to replace mine with one of these. It is the silver colour ones. By the way, electricity is not always stable in my area especially in weather conditions etc and I almost change PSU every year. I don't use a UPS. My cpu is the 6 core Intel i7-8700 with no dGPU. Thank you

*450w
 
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NightHawkRMX

Illustrious
Riotoro Enigma gold 850w.

Fine for a 9900k @stock and rtx2080 super gaming x trio?

My friend badly wanted 850w for under 100. I suggested a focus gold 750w, but he wanted 850w. I hear this psu is pretty alright.

Definitely better than his old tt smart 600w.
 

Aeacus

Glorious
Ambassador

Ma3s7ro

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Nov 5, 2009
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Hey guys, looking to replace my crapy psu. I live in Portugal and the specs will be as follow:

Mobo - MSI B450 gaming plus AC
CPU - 3600x
RAM - 32gb G.Skill Aegis 3000Mhz
Disk - Kingston M.2 NVMe 500gb
GPU - 1060 6gb (will upgrade to Ampere when they arrive next year)

Won't overclock.

Searching this engine
https://www.kuantokusta.pt/informatica/Caixas/Fontes-de-Alimentacao

I wanted something under 100€ reliable and most of all, quiet! Its for a itx Gaming/HTPC rig.

Between 50 to 100€ there's plenty of choice, but from what i've read here and other inumerous foruns i've reduced to Seasonic, Super Flower and Corsair PSU's.

I know RM550x would be the best choise, but its a bit pricier, and i've read that Super Flower Leadex 550w III is also really quiet, along with Seasonic Prime Ultra 550w Gold. Not sure about other Super Flower or Seasonic ones, tough they do have some cheaper ones, like Core GM...

So every part will arrive around this week, so didn't want get hold up by the PSU :p

Thanks
 
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Darkbreeze

Titan
Moderator
Yeah, without knowing what level and power requirements you'll need, it's impossible to say. 550w is probably the safest choice since that's enough for MOST graphics cards these days that aren't fully top tier cards but isn't terribly overkill for something lower end that techncially could get by with a good 450w unit, either.
 

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