# Seasonic G Series V2 550 W



## crmaris (Apr 30, 2014)

Seasonic decided to silently update their G-550 model to add Haswell support. The company did not change the model number, but did add a Haswell-ready badge to the box. The G-550 is an affordable product for users on a tight budget who, want a reliable PSU with great performance for a mid-level system.

*Show full review*


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## steen (May 15, 2014)

Could you confirm the electrolytic Chemi-Cons? They seem to be KY & KZE series instead of KZH.


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## crmaris (May 15, 2014)

thanks for noticing it. It was a typo...


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## racedaemon (May 16, 2014)

I have the original G550 and given the fact i have really good hearing i can hear an annoying high pitched sound from the power supply when standing ~2m from the opened case. Did you notice any sounds from the unit when the PC was off or do you have tools to measure this kind of thing? Would the fact that i probably don't have ground in the outlet cause or aggravate this type of behavior? Did i have bad luck with my unit / is this normal? 

Anyway, nice thorough review that i don't fully understand because of my limited knowledge regarding PSUs and electrics/electronics.


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## crmaris (May 16, 2014)

your PSU makes a coil whine noise. Does it make it under certain conditions? For example try it with another system to check if it insists on producing this noise. Also are you sure that it is the PSU and not your VGA or something else (e.g. some VGAs produce really loud coil whine noise).

If you are 100% sure that it is your PSU then you can RMA it. Mine sample was coil whine free.


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## racedaemon (May 16, 2014)

It is not the VGA as i don't have one yet. 
I thought coil noise occurs only when a component is under load, i once had a 9800GT that squealed when running certain CUDA calculations. The noise form my PSU is much fainter and occurs when the PC is off. It probably happens when the PC is running but the noise is far to faint to hear over the fans.
It is more a minor nuisance than a major problem to warrant the hassle of a RMA. I was just curious what component could generate the noise and if that noise is a sign of poor quality or the first sign of a future problem.


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## crmaris (May 17, 2014)

nope it isn't a sign of poor quality, it can happen even to the best components neither it denotes a possible problem. All coils resonate (in other words produce some noise) but in some cases this noise can be heard by the human ear. This is the case in your PSU. Some times using glue or other materials to stabilize the coil rectifies the problem but not always.


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## racedaemon (May 17, 2014)

Returning somewhat to the topic of reviews. It would be interesting to see in future reviews the measure of background noise inside the anechoic chamber with and without the tested device plugged in. I think silent pc freaks would like this.
My router also has a audible high pitch noise if i get close enough to it, so a PSU is not the only device what could benefit form this type of test. 

Thanks for the answers.


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## buggalugs (May 18, 2014)

The components may be good but I'm sure seasonic has some QA issues. I have a feeling the seasonic branded PSUs are units that didn't pass QA for their major partners like corsair or whoever. I have the original G550 and it has a weird problem. If you put all the mounting screws in the PSU(to the case) the fan is locked at maximum RPM.

 It was a hard problem to solve and I found it kinda by accident but I narrowed it down to one screw, so if you tighten it up the fan revs up to max, if you back the screw off the fan settles back to normal. It seems the screw is making contact with something inside the PSU when it is tightened. How could a company make a screwup like that(npi)? Seasonic offered to replace it but its fking annoying to go through all that bullshit with a brand new unit and yes I was using the screws that came with the PSU so they should be the right length.  In the end I cut back a screw.

 I've read a lot of reports from people who bought a Seasonic PSU for the first time based on the high praise from internet reviewers, only to have some coil whine or some other weird fault.


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## crmaris (May 18, 2014)

racedaemon said:


> Returning somewhat to the topic of reviews. It would be interesting to see in future reviews the measure of background noise inside the anechoic chamber with and without the tested device plugged in. I think silent pc freaks would like this.
> My router also has a audible high pitch noise if i get close enough to it, so a PSU is not the only device what could benefit form this type of test.
> 
> Thanks for the answers.



I can do this since my new umber-hind end (and bloody expensive) sound meter can go very low (around 17 dBA) in the chamber. The only problem however is that from sample to sample there can be huge deviations. For example a PSU with minimal coil whine could do 18-20 dBA in standby or in operation without the fan engaged while one with some whine noise could easily reach 25-30 dBA. So unless I could test many of them my noise measurements for ambient electronic noise won't be concise.


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## crmaris (May 18, 2014)

buggalugs said:


> The components may be good but I'm sure seasonic has some QA issues. I have a feeling the seasonic branded PSUs are units that didn't pass QA for their major partners like corsair or whoever. I have the original G550 and it has a weird problem. If you put all the mounting screws in the PSU(to the case) the fan is locked at maximum RPM.
> 
> It was a hard problem to solve and I found it kinda by accident but I narrowed it down to one screw, so if you tighten it up the fan revs up to max, if you back the screw off the fan settles back to normal. It seems the screw is making contact with something inside the PSU when it is tightened. How could a company make a screwup like that(npi)? Seasonic offered to replace it but its fking annoying to go through all that bullshit with a brand new unit and yes I was using the screws that came with the PSU so they should be the right length.  In the end I cut back a screw.
> 
> I've read a lot of reports from people who bought a Seasonic PSU for the first time based on the high praise from internet reviewers, only to have some coil whine or some other weird fault.



High-end platforms with complex electronics are more prone to coil-whine noise, at least according to my experience. Also LLC resonant converters seem to play a part in this problem.
However I don't believe that a major OEM like Seasonic would sell their good units to the rest brands and keep defective ones to be sold under their own name. This just doesn't make any sense.

Also usually on the net you will find mostly complaints about a product and less praises since if/when something works well then usually people forget its existence and don't mess with it. 
As for you problem I would RMA this unit ASAP. 

Finally coil whine doesn't affect a PSU's reliability in any way, it is just annoying. If you see the internals of the new and super expensive AX1500i you will see tons of glue, which they used just to make sure that no coil whine issues will arise. It is a really difficult problem to deal with and lately it became a real concern to most users since the rest components got quieter and left the PSU exposed. And to make things worse the rest system components also play a significant role in the coil whine issue.


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## buggalugs (May 19, 2014)

Yah, personally I've never had a coil whine issue in 15 years of building my own, using different branded PSUs. Never had coil whine on a GPU or any other component either come to think of it. I guess I've been lucky there. Only one PSU ever failed me, a highend 1200Watt unit.

 Maybe I was unlucky with the Seasonic problem but it seems like a serious problem that should have been picked up during QA


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## crmaris (May 19, 2014)

Try the following to see if you can reduce it

1.  Update the BIOS of the MB
2.  In the BIOS, ENABLE all energy savings modes, S4/S5, standby, etc.
3.  In the BIOS, disable Audio Always On, if it is available.
4.  In VGA set up, disable VSync.
5.  If you use AMD APU (Accelerated Processing Unit), then set the "pending current" to "constant current" of 1.2V.

Also according to a PSU manufacturer who provided me some info on this matter, 

Many MBs are delivered with ErP DISABLED and this also causes the PSU to whine.
In addition, they have noticed that many MBs VRM don't have the proper filtering, so some end users change MB and the coil whine goes away. 

This means that a cheapo mainboard can cause coil whine. (my conclusion)

Also some users tried ferrite cores/rings on the 12V & MB cables and the whine went away.


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## nem (Jun 16, 2014)

crmaris hello bro well im very insterested in this model because i am in the posibility of buy this psu but the model of 750w, there is some selling me this psu of course used but to very good Price , so im wonder which is the diference between the G Series V1(550 W) reviewed in 2012 and the G Series V2(550 W) reviewed in 2014, sorry im dont understand or both psu are the same ?

http://www.techpowerup.com/reviews/Seasonic/G550/3.HTML
http://www.techpowerup.com/reviews/Seasonic/G550_V2/3.html


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## AsRock (Jun 16, 2014)

nem said:


> hello bro well im very insterested in this model because i am in the posibility of buy this psu but the model of 750w, there is some selling me this psu of course used but to very good Price , so im wonder which is the diference between the G Series V1(550 W) reviewed in 2012 and the G Series V2(550 W) reviewed in 2014, sorry im dont understand or both psu are the same ?
> 
> http://www.techpowerup.com/reviews/Seasonic/G550/3.HTML
> http://www.techpowerup.com/reviews/Seasonic/G550_V2/3.html



By thew looks of it ones version 2,  Should be a improved version.  I have a Seasonic X-750 v2 and it's been totally sweet.

It's $140 on newegg at the moment not to bad considering the TPU review it got.
http://www.techpowerup.com/reviews/Seasonic/X-750/1.html


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## nem (Jun 16, 2014)

bro one more question, if were you who gona buy one psu and have two options between

both versions of 750w 

Seasonic SSR-750RM : http://www.seasonicusa.com/G-series-450-550-650.htm

Corsair RM50 : http://www.corsair.com/se-fi/rm-series-rm750-80-plus-gold-certified-power-supply

witch you will buy and why

http://www.techpowerup.com/reviews/Seasonic/G550_V2/11.html

http://www.techpowerup.com/reviews/Corsair/RM650/11.html


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## AsRock (Jun 17, 2014)

It be the Seasonic how ever these reviews are old maybe there is newer versions by now ?.. I like Seasonic my self you get what you pay for although Corsair on some of their units are really nice and some times use Seasonic designs and get to pay a little less.

You buy Seasonic you get just that.. And going by some reviews i would pick none as places like HardOCP say the X series is better and the Corsair failed going by there review.

As i said the review s are old and maybe they have improved them by now
Seasonic 
http://www.hardocp.com/article/2013/10/30/seasonic_gseries_g750_power_supply_review/

That Corsair got bad reviews
http://www.techpowerup.com/reviews/Corsair/RM750/11.html
http://www.hardocp.com/article/2013/11/13/corsair_rm750_750w_power_supply_review/1


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