That’s not how modern mono-rail PSUs work, the 12v power rail is shared between all of the 12v connectors. Theoretically you could draw the full rated load from just the CPU connector… until the wires melt.
That's the case with essentially every PSU with more than one output because real world scenarios essentially never max the draw on every output at once. A PSU designed to be able to do that would have a headline number that was impossible to achieve in the real world at a much higher cost. This is especially the case with the PCIe connectors; where the number of connectors needs to be high enough to handle older cards using multiple 6 pin/75W plugs; but spending the extra few cents to make them all 6+2 connectors to facilitate maximum flexibility in wiring for newer cards using 8pin/150W ones makes it much more usable for consumers.
I have heard that SFX sized PSUs don't respond as well to transient loads when compared to ATX sized PSUs. That you should get a higher wattage SFX PSU to compensate for this. Is there any truth to this?
As badly as the small form factor hurt cooling at high loads and as loud as the fan gets it's a shame they didn't go for an 80+ Titanium spec design. In most cases the price penalty isn't worth it unless you're using very expensive power; but here shaving a a few dozen extra watts of waste heat off would significantly extend the quiet fan range.
You can't just generalize that all small form factor PSUs are not worth it. A good PSU is a good PSU, no matter what size. I have a Corsair 750W SFX PSU, and it's perfectly fine and quiet, despite the SFX size. I do not feel I have compromised in any way compared to a full-size ATX 750W, and indeed, I have benefited from the small size in my ITX case. I think all PSUs, large and small, should be judged by their own strengths & weaknesses.
There is a thing called diminishing returns. The laws of physics can’t be broken via wishful thinking.
Taking one aspect of design far out causes necessary curtailment(s). If those are something a person can live with (such as a deaf person with a loud PSU) that’s fine but the more niche a design is the less appeal/relevance it will have for the majority.
Three-wheel microcars have their niche but it’s not a very big one, no matter how ‘good’ they are. Don’t try to drive them at high speeds and don’t expect much if there is a collision with a larger vehicle. They’re fine when they ‘stay in their lane’. No one is going to put a V-8 turbodiesel into one.
This is NOT diminishing returns. This is so stupid as a comment. There's even smaller form factors. With Gallium Nitrate they get even more efficient. They get quieter because of higher efficiency. More can be titanium and platinum rated. Seasonic even makes a dual twin 700W PSU in an ATX form factor. Stop holding back the norm. People like you would never let the Industry do ANYTHING different.
Putting the word 'not' in caps isn't a substantive rebuttal, nor is the rest of your post.
Higher efficiency is available in larger form factors. And... the maximum size of the fan decreases as form factors shrink – something this article pointed out. Smaller fans make more noise for the same level of cooling, typically, if two fans are designed equally efficiently. That is why ATX cases no longer commonly ship with 80mm fans.
'Stop holding back the norm. People like you would never let the Industry do ANYTHING different.'
What's that got to do with anything? Case size shouldn't be the deciding factor for making SFX and SFX L the norm, the standard. Silverstone and many others are proving you can make high efficiency high watt in a smaller package with zero real loss to anything in quality and performance.
‘This is a strange choice by SilverStone, as the company usually prefers to use sleeve bearing fans because of their lower noise output, even for their top-tier products.’
Sleeve bearing fans have to be mounted vertically for good longevity, according to everything I’ve read. PSUs are always mounted horizontally.
Sleeve bearings are also, as far as I know, efficient with no/very low restriction scenarios (e.g. ‘case’ ‘airflow’ fans) but create very little static pressure. So, using a sleeve fan inside a PSU hardly seems optimal in that way either. Should designers begin to mount them vertically...
FDB and similar ‘modern’ bearings seem to be optimal from both a cooling-per-decibel point of view (with decent, although not always great, static pressure ability) and also can be mounted horizontally.
Ball bearing fans typically are used for the highest static pressure scenarios, such as mounted to dense radiators. How much less restriction does a PSU like this one have?
The bearing type has little to no factor in determining static pressure or air flow of the fan.
Sleeve bearing fans just don't last as long as ball bearings, especially in higher temperatures. There is a NMB comparison sheet even tells you that sleeve bearings will fail to operate above 70c.
"Sleeve bearing is quieter" is an outdated convention. Well made ball bearings can run as quiet as sleeve bearings, but cost goes up with tighter tolerances.
The reason for most static pressure fans using ball bearings or fluid dynamic bearings, is probably because they already require tighter manufacturing tolerances, and using higher quality bearings doesn't increase the BoM by much. Where as air flow fans can be made cheaply by skimping on quality and using a sleeve bearing to compensate for the increased noise of poor weight balance.
'The bearing type has little to no factor in determining static pressure or air flow of the fan.'
I have never seen a sleeve fan that has strong static pressure but I have seen plenty of dual-bearing ball fans that do. They have little space between the blades and, typically, large motor hubs.
I have read a lot of fan reviews and the review results don't match your claims, nor the claims of Samus. I have also purchased a good number of fans and have looked at what's on offer at retail and online. These magical sleeve-bearing static pressure fans are like unicorns.
And... regardless of this debate... Is there someone who wants to argue over my point about sleeve bearing fans needing to be installed vertically in order to have good lifespan?
... making their use in power supplies misguided, since they're not mounted vertically.
Sleeve bearing fans also come in various versions (hydro, hypro, duro, hydralic, FDB, etc...) that may have enhancement made to provide better stability for horizontal uses too. But generally, you'll get the shortest lifespan by mounting a sleeve bearing fan horizontally upside down (airflow blowing upwards).
If you have the same fan design and speed, one with sleeve bearing and one with ball bearing. The air pressure generated from the two fans will be identical. The main demand for higher pressure fans come from server/industrial applications and these are made with ball bearing for longevity and reliability as the priority.
Generally fans designed for high pressure applications have higher top speed (for 120mm fans, usually 2000rpm or more), for which sleeve bearing are not suited for. That's the reason they aren't made because no reputable brand will want to sell a fan that will burn out in a year. The point we were trying to make is that if two fans were to have identical speed, frame, and blade design with the only difference being the bearing used. The pressure generated between the two fans will be identical.
I wish tech sites and people would stop talking about SFX as if it shouldn't just be the standard PSU already. SFX and SFX-L should be every new modern PSU. 1000W shouldn't be surprising. It should be "why do you need 1000w SFX PSU". It should just be the norm of what to expect options wise. Why do we still want huge massive bricks? The entire industry is improving. It's like ignoring M.2 form factor because 3.5" HDDs exist. Why do you need a smaller had drive? See, sounds ridiculous. The same could be said about laptop chargers. They're finally getting smaller on average. Why can't we embrace SFX and SfXL as the norm. The more that is made, the cheaper it gets. The level evens out on price parity with legacy sizes. There are case adapters too. It just makes a huge amount of sense. Even in a big case, you still save volume. I'm using SFX in a Rosewill 4U for example. The adapter from Silverstone gives it more air vents in the same space. It's great. It's nothing unusual. Plus another thing with higher watts is it's the only way to get more SATA power ports.
Considering this is the first 1000W SFX-L PSU to market, doesn't seem like the market's ready for an SFX/SFX-L norm yet. As more consumers/enthusiasts demand smaller PSUs, which doesn't seem far-fetched, more momentum will develop in that direction, but we're not there yet.
EasySteel China is a Leading China Hastelloy blend supplier . We believe in credit and quality first. we offer in an assortment of approaches including pipe fittings, bar, sheet, expansion joints. wire, plate, forgings, and a short time later a few.<a href="https://easysteelsh.com/project/plate/">Ch... rolled clad plate</a>
This is the only SFX PSU actually able to power a (read: one) 3090 GPU.
A couple of months ago I built a watercooled 5800X+3090FE system in a DAN A4 case (wiith external radiators, will not discuss "y tho?") and the Silverstone SX800-LTI PSU shut down consistently in various games, if I did not limit the power limit on the 3090 to ~80%. When I put this 1000W PSU in, all problems gone.
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shabby - Wednesday, July 28, 2021 - link
6 pci-e 8pin = 900 watts, that leaves 100 watts for the cpu? 🤔Charlie22911 - Wednesday, July 28, 2021 - link
That’s not how modern mono-rail PSUs work, the 12v power rail is shared between all of the 12v connectors. Theoretically you could draw the full rated load from just the CPU connector… until the wires melt.shabby - Wednesday, July 28, 2021 - link
Yes yes that I know, it just seems that you can fully utilize all the connectors at full load.shabby - Wednesday, July 28, 2021 - link
Can't... wheres that edit button!DanNeely - Thursday, July 29, 2021 - link
That's the case with essentially every PSU with more than one output because real world scenarios essentially never max the draw on every output at once. A PSU designed to be able to do that would have a headline number that was impossible to achieve in the real world at a much higher cost. This is especially the case with the PCIe connectors; where the number of connectors needs to be high enough to handle older cards using multiple 6 pin/75W plugs; but spending the extra few cents to make them all 6+2 connectors to facilitate maximum flexibility in wiring for newer cards using 8pin/150W ones makes it much more usable for consumers.meacupla - Wednesday, July 28, 2021 - link
Is anandtech capable of testing transient loads?I have heard that SFX sized PSUs don't respond as well to transient loads when compared to ATX sized PSUs. That you should get a higher wattage SFX PSU to compensate for this. Is there any truth to this?
DanNeely - Wednesday, July 28, 2021 - link
As badly as the small form factor hurt cooling at high loads and as loud as the fan gets it's a shame they didn't go for an 80+ Titanium spec design. In most cases the price penalty isn't worth it unless you're using very expensive power; but here shaving a a few dozen extra watts of waste heat off would significantly extend the quiet fan range.supdawgwtfd - Thursday, July 29, 2021 - link
It could be extra capacitors killing the power efficiency but as has been mentioned help transient loads.Just pure shit talking though.
Leeea - Wednesday, July 28, 2021 - link
Small form factor is just not worth the compromise.Wereweeb - Wednesday, July 28, 2021 - link
For you*romrunning - Wednesday, July 28, 2021 - link
You can't just generalize that all small form factor PSUs are not worth it. A good PSU is a good PSU, no matter what size. I have a Corsair 750W SFX PSU, and it's perfectly fine and quiet, despite the SFX size. I do not feel I have compromised in any way compared to a full-size ATX 750W, and indeed, I have benefited from the small size in my ITX case. I think all PSUs, large and small, should be judged by their own strengths & weaknesses.Oxford Guy - Wednesday, July 28, 2021 - link
There is a thing called diminishing returns. The laws of physics can’t be broken via wishful thinking.Taking one aspect of design far out causes necessary curtailment(s). If those are something a person can live with (such as a deaf person with a loud PSU) that’s fine but the more niche a design is the less appeal/relevance it will have for the majority.
Three-wheel microcars have their niche but it’s not a very big one, no matter how ‘good’ they are. Don’t try to drive them at high speeds and don’t expect much if there is a collision with a larger vehicle. They’re fine when they ‘stay in their lane’. No one is going to put a V-8 turbodiesel into one.
CheapSushi - Thursday, July 29, 2021 - link
This is NOT diminishing returns. This is so stupid as a comment. There's even smaller form factors. With Gallium Nitrate they get even more efficient. They get quieter because of higher efficiency. More can be titanium and platinum rated. Seasonic even makes a dual twin 700W PSU in an ATX form factor. Stop holding back the norm. People like you would never let the Industry do ANYTHING different.Oxford Guy - Thursday, July 29, 2021 - link
Putting the word 'not' in caps isn't a substantive rebuttal, nor is the rest of your post.Higher efficiency is available in larger form factors. And... the maximum size of the fan decreases as form factors shrink – something this article pointed out. Smaller fans make more noise for the same level of cooling, typically, if two fans are designed equally efficiently. That is why ATX cases no longer commonly ship with 80mm fans.
'Stop holding back the norm. People like you would never let the Industry do ANYTHING different.'
Good ole ad hom... the lubricant of astroturf.
Samus - Thursday, July 29, 2021 - link
What compromise? Not everyone needs a big case to flex their e-peen :)CheapSushi - Thursday, July 29, 2021 - link
What's that got to do with anything? Case size shouldn't be the deciding factor for making SFX and SFX L the norm, the standard. Silverstone and many others are proving you can make high efficiency high watt in a smaller package with zero real loss to anything in quality and performance.Oxford Guy - Thursday, July 29, 2021 - link
Oh my. Well... you managed to respond to a bad comment with one that was even less competent.Oxford Guy - Wednesday, July 28, 2021 - link
‘This is a strange choice by SilverStone, as the company usually prefers to use sleeve bearing fans because of their lower noise output, even for their top-tier products.’Sleeve bearing fans have to be mounted vertically for good longevity, according to everything I’ve read. PSUs are always mounted horizontally.
Sleeve bearings are also, as far as I know, efficient with no/very low restriction scenarios (e.g. ‘case’ ‘airflow’ fans) but create very little static pressure. So, using a sleeve fan inside a PSU hardly seems optimal in that way either. Should designers begin to mount them vertically...
FDB and similar ‘modern’ bearings seem to be optimal from both a cooling-per-decibel point of view (with decent, although not always great, static pressure ability) and also can be mounted horizontally.
Ball bearing fans typically are used for the highest static pressure scenarios, such as mounted to dense radiators. How much less restriction does a PSU like this one have?
meacupla - Thursday, July 29, 2021 - link
The bearing type has little to no factor in determining static pressure or air flow of the fan.Sleeve bearing fans just don't last as long as ball bearings, especially in higher temperatures.
There is a NMB comparison sheet even tells you that sleeve bearings will fail to operate above 70c.
"Sleeve bearing is quieter" is an outdated convention. Well made ball bearings can run as quiet as sleeve bearings, but cost goes up with tighter tolerances.
The reason for most static pressure fans using ball bearings or fluid dynamic bearings, is probably because they already require tighter manufacturing tolerances, and using higher quality bearings doesn't increase the BoM by much.
Where as air flow fans can be made cheaply by skimping on quality and using a sleeve bearing to compensate for the increased noise of poor weight balance.
Oxford Guy - Thursday, July 29, 2021 - link
'The bearing type has little to no factor in determining static pressure or air flow of the fan.'I have never seen a sleeve fan that has strong static pressure but I have seen plenty of dual-bearing ball fans that do. They have little space between the blades and, typically, large motor hubs.
I have read a lot of fan reviews and the review results don't match your claims, nor the claims of Samus. I have also purchased a good number of fans and have looked at what's on offer at retail and online. These magical sleeve-bearing static pressure fans are like unicorns.
patrickjp93 - Friday, July 30, 2021 - link
Noctua and Nidec Servo would like words with you. SSO2 bearings ARE sleeve bearings.Oxford Guy - Tuesday, August 3, 2021 - link
If they can be mounted horizontally they’re not sleeve bearing fans.Samus - Thursday, July 29, 2021 - link
blade shape and shroud design dictate pressure and velocity. bearing has nothing to do with it.Oxford Guy - Thursday, July 29, 2021 - link
Tell that to the manufacturers, then. They don't produce sleeve bearing fans with high static pressure in mind.Oxford Guy - Thursday, July 29, 2021 - link
And... regardless of this debate... Is there someone who wants to argue over my point about sleeve bearing fans needing to be installed vertically in order to have good lifespan?... making their use in power supplies misguided, since they're not mounted vertically.
tonyou - Friday, July 30, 2021 - link
Sleeve bearing fans also come in various versions (hydro, hypro, duro, hydralic, FDB, etc...) that may have enhancement made to provide better stability for horizontal uses too. But generally, you'll get the shortest lifespan by mounting a sleeve bearing fan horizontally upside down (airflow blowing upwards).Oxford Guy - Tuesday, August 3, 2021 - link
FDB fans and those other types are not what I have been discussing.I have been discussing true/classic sleeve designs, the kind that must be mounted vertically.
Don’t move the goal posts.
tonyou - Friday, July 30, 2021 - link
If you have the same fan design and speed, one with sleeve bearing and one with ball bearing. The air pressure generated from the two fans will be identical. The main demand for higher pressure fans come from server/industrial applications and these are made with ball bearing for longevity and reliability as the priority.Oxford Guy - Tuesday, August 3, 2021 - link
Post one example of a high static pressure classic sleeve bearing fan.tonyou - Friday, September 3, 2021 - link
Generally fans designed for high pressure applications have higher top speed (for 120mm fans, usually 2000rpm or more), for which sleeve bearing are not suited for. That's the reason they aren't made because no reputable brand will want to sell a fan that will burn out in a year.The point we were trying to make is that if two fans were to have identical speed, frame, and blade design with the only difference being the bearing used. The pressure generated between the two fans will be identical.
CheapSushi - Thursday, July 29, 2021 - link
I wish tech sites and people would stop talking about SFX as if it shouldn't just be the standard PSU already. SFX and SFX-L should be every new modern PSU. 1000W shouldn't be surprising. It should be "why do you need 1000w SFX PSU". It should just be the norm of what to expect options wise. Why do we still want huge massive bricks? The entire industry is improving. It's like ignoring M.2 form factor because 3.5" HDDs exist. Why do you need a smaller had drive? See, sounds ridiculous. The same could be said about laptop chargers. They're finally getting smaller on average. Why can't we embrace SFX and SfXL as the norm. The more that is made, the cheaper it gets. The level evens out on price parity with legacy sizes. There are case adapters too. It just makes a huge amount of sense. Even in a big case, you still save volume. I'm using SFX in a Rosewill 4U for example. The adapter from Silverstone gives it more air vents in the same space. It's great. It's nothing unusual. Plus another thing with higher watts is it's the only way to get more SATA power ports.whaletail - Sunday, August 1, 2021 - link
Considering this is the first 1000W SFX-L PSU to market, doesn't seem like the market's ready for an SFX/SFX-L norm yet. As more consumers/enthusiasts demand smaller PSUs, which doesn't seem far-fetched, more momentum will develop in that direction, but we're not there yet.Oxford Guy - Wednesday, August 11, 2021 - link
‘doesn't seem like the market's ready for an SFX/SFX-L norm yet’Umm... what reality is ready for is wattage that conforms to the laws of physics in a practical manner.
Oxford Guy - Wednesday, August 11, 2021 - link
That said... better heatsinks may have helped. Better efficiency (‘titanium’). A better fan.Most importantly, though... not using power pigs like Rocket Lake and thus having no need to try to stuff 1000 watts into a small form factor.
easysteelchina - Friday, August 13, 2021 - link
EasySteel China is a Leading China Hastelloy blend supplier .We believe in credit and quality first. we offer in an assortment of approaches including pipe fittings,
bar, sheet, expansion joints. wire, plate, forgings, and a short time later a few.<a href="https://easysteelsh.com/project/plate/">Ch... rolled clad plate</a>
besterino - Tuesday, August 24, 2021 - link
This is the only SFX PSU actually able to power a (read: one) 3090 GPU.A couple of months ago I built a watercooled 5800X+3090FE system in a DAN A4 case (wiith external radiators, will not discuss "y tho?") and the Silverstone SX800-LTI PSU shut down consistently in various games, if I did not limit the power limit on the 3090 to ~80%. When I put this 1000W PSU in, all problems gone.
Fuckman4 - Monday, August 1, 2022 - link
I don't know why all Silverstone PSUs have a high ripple even in Titanium models!I have to wait for ROG LOKI for reasonable output quality.