Power Supply SX-700-LPT vs BeQuiet! SFX-L

VladTheImplier

Efficiency Noob
Original poster
Mar 28, 2018
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Hey,
I'm building a workstation and looking for a quiet SFX-L PSU in the 600W range. Based on the reviews on this site, the SX-700-LPT seems to be the most quiet 600W+ PSU (at least till 500W load as stated by the review).
According to the Noise section from the Lian-Li PE 750 review the SX-700-LPT doesn't turn on until 350W. Contrary to this the review over at JonnyGuru states that "You need to run this unit below the fanless threshold (150W) [...]".
With this site's remarks on Fan ratter I'm undecided.

With the BeQuiet! 600W version being out, being based on the same platform, with people in this forum mentioning, that it is most likely quiter due to being the same platform with lower wattage, this seems to be the smarter choice.

However, I have yet to find a review about the noise specifically, that is as good as the review on this site are.
Only Noise pressure levels based on standardized tests, not taking into account the subjective details like rattle.

Does anyone have experience with both the BeQuiet! SFX-L 600W and the SF700-LPT? Could someone recommend one over the other based on noise?
 

jmarin

Airflow Optimizer
Mar 8, 2018
258
187
Unless you're fully committed to an SFX-L PSU, I'd recommend the Corsair SF600 SFX PSU. I don't have experience with the two you are specifically asking about though, sorry.
 

VladTheImplier

Efficiency Noob
Original poster
Mar 28, 2018
7
0
Unless you're fully committed to an SFX-L PSU [...]
I'm not, I have plenty of space either way. If the SX600 is better in terms of noise, I would gladly take it.
But isn't a SFX PSU gonna be louder than a SFX-L PSU? I mean we are talking about a 92mm vs a 120mm fan.
 

jmarin

Airflow Optimizer
Mar 8, 2018
258
187
I'm not, I have plenty of space either way. If the SX600 is better in terms of noise, I would gladly take it.
But isn't a SFX PSU gonna be louder than a SFX-L PSU? I mean we are talking about a 92mm vs a 120mm fan.
Corsair's SF450 and SF600 are super quiet and highly rated. Unless I needed over 600 watts I wouldn't use anything else
 

VladTheImplier

Efficiency Noob
Original poster
Mar 28, 2018
7
0
Corsair's SF450 and SF600 are super quiet and highly rated.
So why even invent a SFX-L category :p
According to this reddit thread, that compares the Corsair SF600 with the BeQuiet! 600W SFX-L the consensus in the comments appears to be, that if size is no issue, the noise is undoubtfully better with the beQuiet! one:

"Honestly, I have a SF600, and while it is nice in zero-RPM mode, when the temp kicks up and the fan goes on, its by far the loudest part of my system."

Which is why I would still stick to the SFX-L ones and am looking for a answer on noise between these two and what reviewer got the Zero-RPM range of the SF700-LPT (350W or 180W) right. Maybe different revisions, since Jonny mentioned Silverstone being on it to fix the Fan controller issue of his review.
 

SilverStone

Caliper Novice
SilverStone
Jan 5, 2017
33
114
If space is not an issue for you, SFX-L will be generally quieter the higher you go in power draw compared to a standard SFX unit. There is just no getting around the fan size disadvantage of a 92mm fan in the smaller unit vs. 120mm in the SFX-L.

SX700-LPT's zero rpm range is applicable up to around 150W of power draw. A little known fact about SX700-LPT is that we updated its fan to FDB (Fluid Dynamic Bearing) and started shipping these in early 2017. So any SX700-LPT review published before the first half of 2017 may not be representative of the ones you'll be able to buy now.
 

SilverStone

Caliper Novice
SilverStone
Jan 5, 2017
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Not anytime soon, the SX800-LTI is already our second most power dense consumer PSU (775W per liter). The current leader in power density is our standard SFX SX650-G at 819W per liter so if you translate that density into SFX-L, you'd be looking at about 845W. If we are on target with our development trajectory, a SFX-L PSU with 1000W may not be technically possible until another 3 or 4 years. And that's just the technical part of the hurdle.

The other is the business hurdle. SX700-LPT and SX800-LTI are already niche products within the somewhat niche SFX/SFX-L enthusiasts PSU market and their sales numbers reflect that. We sell fractions of these compared with 500W or lower SFX/SFX-L models and there's a chance their development costs may not be paid back within reasonable time. So when it does become technically possible to create a 1000W SFX-L PSU, we'll have to ask ourselves if there's a market large enough to support it? From the current sales of SX800-LTI, that answer is probably a no.

With that said, also want to mention that SX800-LTI was updated in the middle of last year as well. So now all available new units should have dual ball bearing fan instead of sleeve bearing fan as seen in earlier reviews.
 

tinyitx

Shrink Ray Wielder
Jan 25, 2018
2,279
2,338
With that said, also want to mention that SX800-LTI was updated in the middle of last year as well. So now all available new units should have dual ball bearing fan instead of sleeve bearing fan as seen in earlier reviews.

Is there a way a consumer can check on the outside of the package (eg a certain range of the serial number) of a SX800-LTI or SX700-LPT to determine whether it is an updated version (ie using dual ball bearing) or an older version (ie using sleeve bearing fan)? Or, is there a box sticker identifying its fan is dual ball bearing?

Edit#1
How about your SX650-G? Has it received the same fan upgrade?
 
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VladTheImplier

Efficiency Noob
Original poster
Mar 28, 2018
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SX700-LPT's zero rpm range is applicable up to around 150W of power draw.
Interesting, so JohhnyGuru was correct and this site's review is slightly incorrect
Is there a way a consumer can check on the outside of the package (eg a certain range of the serial number) of a SX800-LTI or SX700-LPT to determine whether it is an updated version
Makes me wonder as well. The update to a Fluid Dynamic bearing, as mentioned in SilverStone's post would elevate the PSU quite a bit. A way to tell them apart is important.
 

SilverStone

Caliper Novice
SilverStone
Jan 5, 2017
33
114
Is there a way a consumer can check on the outside of the package (eg a certain range of the serial number) of a SX800-LTI or SX700-LPT to determine whether it is an updated version (ie using dual ball bearing) or an older version (ie using sleeve bearing fan)? Or, is there a box sticker identifying its fan is dual ball bearing?

Edit#1
How about your SX650-G? Has it received the same fan upgrade?

If you haven't noticed already, both SX800-LTI and SX700-LPT product pages now include a note below the specification table telling you which starting serial numbers indicate models with updated fans.

For SX650-G and SX500-G, they were already using FDB fans from the very beginning.
 
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SilverStone

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SilverStone
Jan 5, 2017
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ohh, wait, is there a difference? Dual ball bearing vs Fluid dynamic?

Yes, they are different bearing technologies and their intended usage are different as well. Dual ball bearings are mostly used in fans that need to last a long time or operating in higher temperature environments. It is however generally louder compared to sleeve bearing based fans. FDB (Fluid Dynamic Bearing) fans are similarly as quiet as sleeve bearing fans but with better durability that come close or equal to ball bearing based fans in normal environments.

There are quite a lot of articles on the net about these fans if you are curious and want to know more about them. For FDB fans, there are some disagreements in regards to what can be considered FDB, so check out the article by Hardware Secrets for more detail on that. We belong in the camp of manufacturers that believe only the patented Matsushita design can be called FDB:
http://www.hardwaresecrets.com/the-truth-about-fluid-dynamic-bearing-fdb-fans/
 

tinyitx

Shrink Ray Wielder
Jan 25, 2018
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If you haven't noticed already, both SX800-LTI and SX700-LPT product pages now include a note below the specification table telling you which starting serial numbers indicate models with updated fans.

For SX650-G and SX500-G, they were already using FDB fans from the very beginning.
Excellent! Corsair SF600 has been out of stock for at least 4 months locally. In a few months, I will begin a new build. I am looking at SX650-G and SX700-LPT now. Thanks for the info.:thumb:

Edit: I just searched SX700-LPT pics online and it seems the S/N is on a sticker on the PSU and is not shown on the box. Am I right? If so, then this is not too helpful. I also notice there is a V1.0 sticker on both the box and on the PSU. Would it be V1.1 or V2.0 for the models with updated fan?
 
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SilverStone

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SilverStone
Jan 5, 2017
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I just searched SX700-LPT pics online and it seems the S/N is on a sticker on the PSU and is not shown on the box. Am I right?

No, there is always serial number stickers on both the PSU and the retail box.

The retail box serial number sticker is located on the back of the retail box as shown in photo below, both SX700-LPT and SX800-LTI serial numbers starts with just numbers, no letters in front:
 
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VladTheImplier

Efficiency Noob
Original poster
Mar 28, 2018
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No, there is always serial number stickers on both the PSU and the retail box.
Thanks for the good information.
The updated fan completly reversed my buying decison form the BeQuiet to the Silverstone one, (after having a PSU with fan rattling in the past specifically, the observation of slight fan rattle from this sites review was a turn off)

But the amount of digging to get that info is unreal.
If not already, you should contact reviewers to get such info out, like in an one sentence Update at the end of reviews.
Would be great if there was a:
Silverstone came forward with a statement, that claims all models have been updated since 2017, with a fluid dynamic bearing fan.
Also they commented, that the starting fan load is 150W, not the 350W as we deduced from our test.
 

SilverStone

Caliper Novice
SilverStone
Jan 5, 2017
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Thanks for the good information.
The updated fan completly reversed my buying decison form the BeQuiet to the Silverstone one, (after having a PSU with fan rattling in the past specifically, the observation of slight fan rattle from this sites review was a turn off)

The perception that the fan rattled in some of our earlier SFX-L PSUs was due to the optical illusion created by the shinny, glossy fan blades. With very high light reflection added to a spinning fan, it created the appearance of fan blades moving up and down. But in actuality, the fans did not move or rattle. This is also the reason why newer fans in our SFX-L models changed to non-glossy material to avoid misunderstanding like this.
 
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smitty2k1

King of Cable Management
Dec 3, 2016
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Excellent! Corsair SF600 has been out of stock for at least 4 months locally. In a few months, I will begin a new build. I am looking at SX650-G and SX700-LPT now. Thanks for the info.:thumb:

Edit: I just searched SX700-LPT pics online and it seems the S/N is on a sticker on the PSU and is not shown on the box. Am I right? If so, then this is not too helpful. I also notice there is a V1.0 sticker on both the box and on the PSU. Would it be V1.1 or V2.0 for the models with updated fan?

I'm very happy with my SX650-G. I was using the ST45SF-G (with Noiseblocker fan mod) for several years for my 4770k and GTX 780 superclock. When I upgraded my GTX 780 to Vega 56 my computer started crashing. I figured it must be the power draw from the Vega so I replaced my 450w Silverstone with the 650w Silverstone. The crashing continued, but it turned out that disabling my motherboard's anti-surge fixed it (and the Vega still ran on my 450w PSU). I guess the Asus implementation of anti-surge does not play nicely with the Vega graphics cards.

Anyways, the SX650-G has plenty of connectors, plenty of power, and is quiet (enough) for my needs and takes up less space than an SFX-L form factor. Easy choice for me.
 
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