Other How to reduce cable clutter to a minimum

iFreilicht

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We all know about the 24pin problem. There's this one, unbelieviably bulky cable in our machines that supplies the mainboard with power. It takes up an unnecessary amount of space, is hard to route and in general hinders the advancement of SFF (a little bit).

Some of us already imagined a hypothetical new connector with ~8 pins that would still provide the same functionality and enough performance for ITX boards. But the adoption of something like that would be a chicken-and-egg situation.

But what if there was a different solution?

Some propsed to use thin mITX, but that form factor seems to be pretty much dead for consumers.

With modular SFX(-L) and FlexATX PSUs, what would prevent us from connecting a PicoPSU to an internal PSU like the PicoPSU-160-XT? There is the problem with the #PS_ON signal, but that should be resolvable somehow. If we can deal with that, we would get the advantage of thin mITX with just two wires from PSU to mainboard but could still use high-powered CPUs and any Mainboard on the market. This would also work for mATX boards.

How strong would the Pico have to be anyway? It doesn't regulate the 12V and peripherals might be connected to the main PSU anyway.

Is this a viable idea? Is the ATX24pin cable really that big of a deal to justify something like this?
 

Phuncz

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In theory, PSU manufacturers could negate the chicken-and-egg problem by using ATX-24pin to "ITX-8pin" adapters on the end of cable to the PSU's 8-pin receptacle. If they would use the slimline ATX-24pin connectors the PicoPSUs use, the adapter wouldn't have to be overly bulky either. But for this to be more than a one-off project and not be just about adapters forever, you'd need a PSU and motherboard brand that sees the necessity for this and be willing to try this.

But there is probably more to it, like certification issues or costs I'd guess.

Your idea of using a PicoPSU seems valid, although I'd desolder the SATA and 4-pin Molex connectors.
Do consumer mITX boards need 8-pin EPS connectors to work or is it just for potentially more stable overclocking ?
 

Ceros_X

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Anecdotal, but when I was researching ITX boards I noticed that any Z170 board that didn't have an 8 pin EPS connector had a huge list of negative reviews where people claimed it throttled back while attempting to OC. It is the main reason I went with the board I did.

Back on topic, I think the best place to get something like this done would be with HDPlex or the Pico PSU guys. I think if we could get them to do a small run of SFX PSUs with small improvements directed directly at SFF builders we could help nudge the major producers to adopt them.

Things I think would improve cabling:

* SFX or Flex ATX PSU where the PSU side connector was modular and flush with the side of the PSU.

* The 24-pin cable was not sold with the PSU, and was instead purchased seperately, with lengths available in 1.5 or 2 inch increments. i.e 2", 4", 6", etc builds. Just being able to get the exact cable length needed would drastically decrease cable clutter. I know it wouldn't be as cheap (vs mass producing one size) but I know I'd happily pay for the chance to skip modding shit myself as long as it wasn't at the cost of custom cabling sold elsewhere. (I.e $100 etc).

* Slimeline ATX connectors on the PSU side if it would help recover internal space from recessed modular connector?

* Develop right angled motherboard-side ATX connectors, either by default or as an included adapter with all ATX cords. These would be L shaped pins with the row closest to the board's edge being shorter than the pins furthest from the board's edge. This would help eliminate the 'cable curve' that adds to cable bulk and the cluttered look we all hate.

*Option for unterminated mobo side cable with connector and pins included? Cables with pinoit number printed on sheathing?

* Not related to this but semi-fanless modes and maximizing cooling fan used (top mounted for FlexAtx, 92mm+ for SFX) should be mandatory.

I think any of these options would go a long way towards reducing the cabling anaconda that is the 24 pin atx connection and maybe cause PSU companies to strive to improve more.
 

iFreilicht

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Your idea of using a PicoPSU seems valid, although I'd desolder the SATA and 4-pin Molex connectors.
Do consumer mITX boards need 8-pin EPS connectors to work or is it just for potentially more stable overclocking ?

That's why I mentioned the 160-XT specifically. It is a modular unit:



So for this to work, you'd only need an cable from the ATX 24pin to the Pico, no modding required. That's why it seems like such an interesting idea.

From what I know, quite a few boards make sure that power is supplied through that port, even if it's connected directly to the 12V input of the ATX connector, just to make sure everything will work.

Back on topic, I think the best place to get something like this done would be with HDPlex or the Pico PSU guys. I think if we could get them to do a small run of SFX PSUs with small improvements directed directly at SFF builders we could help nudge the major producers to adopt them.

Why would we consults Mini-Box or HDPLEX? Neither of them have any experience with SFX PSUs so far.

Things I think would improve cabling:

* SFX or Flex ATX PSU where the PSU side connector was modular and flush with the side of the PSU.

Both form factors have flush modular connectors already. The SSP-300SUGs connector, even the one on the cable, is 100% inside the bounding box of FlexATX, there is at least one SFX unit with flush connectors as well.

* The 24-pin cable was not sold with the PSU, and was instead purchased seperately, with lengths available in 1.5 or 2 inch increments. i.e 2", 4", 6", etc builds. Just being able to get the exact cable length needed would drastically decrease cable clutter. I know it wouldn't be as cheap (vs mass producing one size) but I know I'd happily pay for the chance to skip modding shit myself as long as it wasn't at the cost of custom cabling sold elsewhere. (I.e $100 etc).

That seems interesting, but I think the cost of the cable would rise to a point where most people wouldn't bother purchasing in the first place. It's more likely that custom cabling companies will adapt the ribbon cabling that Silverstone uses on their PSUs, which already helps a great deal from what I've heard.

* Slimeline ATX connectors on the PSU side if it would help recover internal space from recessed modular connector?

The slimline connector is only made as the female part, the one that plugs into the Mainboard or PSU. So no, wouldn't help.

* Develop right angled motherboard-side ATX connectors, either by default or as an included adapter with all ATX cords. These would be L shaped pins with the row closest to the board's edge being shorter than the pins furthest from the board's edge. This would help eliminate the 'cable curve' that adds to cable bulk and the cluttered look we all hate.

Actually, those connectors exist and mainboard manufacturers could use those instead of straight ones. That would of course break compatibility with a lot of cases, so they don't.
An adapter seems like a good idea at first, but you're not really saving any space with that. The cable only extends upwards from the board anyway, and plugging it into a right angle adapter would require more space in front of the board, where you might not have it.

*Option for unterminated mobo side cable with connector and pins included? Cables with pinoit number printed on sheathing?

At that point, just crimping the cable yourself completely would make more sense. Printed numbers on the cables would cost an awful lot of money, but some sort of cable comb would be imaginable.

* Not related to this but semi-fanless modes and maximizing cooling fan used (top mounted for FlexAtx, 92mm+ for SFX) should be mandatory.

Allowing additional mounting points for fans on a PSU is a no-go. The tests that the manufacturer makes to ensure the flawless functionality of the PSU are only valid with the exact configuration they were conducted in. A top mounted fan on a FlexATX PSU would have to be preinstalled, certified and tested. At that point it's pretty much a proprietary format and would cost a lot to produce in small runs. PSUs with 92mm fans on SFX already exist, don't they?

I think any of these options would go a long way towards reducing the cabling anaconda that is the 24 pin atx connection and maybe cause PSU companies to strive to improve more.

Only agreeing on the modular cables with you there. Those are the most important way to reduce the clutter and make the cabling runs as clean as possible.
 

Dedaciai

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Jan 31, 2016
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This is totally not related to 24-Pin power cable, but one thing I did was move to an M.2 SSD. Obviously, your MB will have to support M.2 and your storage needs may warrant a big HDD or SSD by as a primary drive it'll take away a power cable (depending on your PSU) and SATA cable.
 

Ceros_X

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Mar 8, 2016
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Why would we consults Mini-Box or HDPLEX? Neither of them have any experience with SFX PSUs so far.

We would ask them because both of them are active on this forum and actively soliciting opinions on how to make better, more appealing products which makes it more likely they would implement something vs a much larger, more experienced company like say, Corsair, which does have a presence on the board but where new products require much more internal momentum to reach production. I believe you personally have worked with HD-Plex engineers on issues, no? They are also experts in small run production of PSU related items, which this hypothetical PSU would most likely be.

Both form factors have flush modular connectors already. The SSP-300SUGs connector, even the one on the cable, is 100% inside the bounding box of FlexATX, there is at least one SFX unit with flush connectors as well.
As you said though, it is modular in that you can remove the plug, but many wires are joined together so it is an all or nothing thing.


That seems interesting, but I think the cost of the cable would rise to a point where most people wouldn't bother purchasing in the first place. It's more likely that custom cabling companies will adapt the ribbon cabling that Silverstone uses on their PSUs, which already helps a great deal from what I've heard.
I think most of the modular cabling prices (ala cable configurator and other sites) are done by hand to order, correct? That is why you see some of the crazy prices. I think that something produced in China where all you are changing is wire length could be feasible at reasonable prices. If you have already investigated this I will defer to you, however.


Actually, those connectors exist and mainboard manufacturers could use those instead of straight ones. That would of course break compatibility with a lot of cases, so they don't.
An adapter seems like a good idea at first, but you're not really saving any space with that. The cable only extends upwards from the board anyway, and plugging it into a right angle adapter would require more space in front of the board, where you might not have it.

I came across the adapters when I was originally posting my reply, so it looks like it would be easiest to go the adapter route. That said, if it saves vertical space and leads to a straighter run for a low cost, why not have the option? That is in the true spirit of a modular PSU to be sure. Working on a height restricted scratch build I know I would have apreciated it.

At that point, just crimping the cable yourself completely would make more sense. Printed numbers on the cables would cost an awful lot of money, but some sort of cable comb would be imaginable.
A cable comb is a good idea. If you've done the research on printed cables then again, I'll defer to you.


Allowingadditional mounting points for fans on a PSU is a no-go. The tests that the manufacturer makes to ensure the flawless functionality of the PSU are only valid with the exact configuration they were conducted in. A top mounted fan on a FlexATX PSU would have to be preinstalled, certified and tested. At that point it's pretty much a proprietary format and would cost a lot to produce in small runs. PSUswith 92mm fans on SFX already exist, don't they?

I was speaking of replacing the 40mm front fan with an 80mm top fan at the mfg. As I am speaking of making a new PSU incorporating all of the ideas, the cost would be built into the product regardless. Do all of the various DC ATX PSUs sold on Ali have these expensive certifications and are they required if sold from the Chinese manufacturer straight to the consumer? 92mm fans do exist, as do semifanless modes - I'm looking for a product that would incorporate as many changes as possible to reduce cable clutter.

I like where you are going with the Pico to ATX 24 (PAX24?) adapter, I guess I'm just trying to spit ball different ways of reducing cable clutter without going that route. If you were going to introduce the perfect SFF SFX or FlexATX PSU, what would it do differently?
 

iFreilicht

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This is totally not related to 24-Pin power cable, but one thing I did was move to an M.2 SSD. Obviously, your MB will have to support M.2 and your storage needs may warrant a big HDD or SSD by as a primary drive it'll take away a power cable (depending on your PSU) and SATA cable.

Jup, very important. If you're going to buy just a single SSD, go for mSATA/M.2. Makes cabling a good bit easier.

We would ask them because both of them are active on this forum and actively soliciting opinions on how to make better, more appealing products which makes it more likely they would implement something vs a much larger, more experienced company like say, Corsair, which does have a presence on the board but where new products require much more internal momentum to reach production. I believe you personally have worked with HD-Plex engineers on issues, no? They are also experts in small run production of PSU related items, which this hypothetical PSU would most likely be.

That's a good point, actually. Especially HDPLEX themselves already sell (low-power) ACDC PSUs, so maybe might be a good company to do this sort of thing.
Actually I just asked them questions about their product, nothing more.

As you said though, it is modular in that you can remove the plug, but many wires are joined together so it is an all or nothing thing.

True.

I think most of the modular cabling prices (ala cable configurator and other sites) are done by hand to order, correct? That is why you see some of the crazy prices. I think that something produced in China where all you are changing is wire length could be feasible at reasonable prices. If you have already investigated this I will defer to you, however.

Yes, cable configurator cables are made by hand, but they're also always sleeved IIRC, so there's a lot more work to be done for their cables.

We're both just guessing in this area, but you are correct that manufacturing in Asia could very well drop the price to something managable. The problem I'm seeing is the low number of units that will be sold. Even if you sell 300 PSUs, the more cable lengths you offer, the fewer will be bought per length, and that always increases the price per unit.
So you either have to know which cable lengths will be bought in advance or buy more than needed and sit on a few spare ones.

I came across the adapters when I was originally posting my reply, so it looks like it would be easiest to go the adapter route. That said, if it saves vertical space and leads to a straighter run for a low cost, why not have the option? That is in the true spirit of a modular PSU to be sure. Working on a height restricted scratch build I know I would have apreciated it.

Do you have a link?
Does it really save vertical space, though? The ATX cable can always be bent so that it's not taller than the rear audio ports. I'm having a hard time finding a situation where this adapter would actually make cabling easier. I understand that you have to bend it less, but you'll have to bend the cable anyway and it's not going to change how thick it's going to be.

A cable comb is a good idea. If you've done the research on printed cables then again, I'll defer to you.

Again, I didn't, but I do know that the material price for cables is coming from the extreme amount of meters and kilometers that are being spit out by the factories.

I was speaking of replacing the 40mm front fan with an 80mm top fan at the mfg. As I am speaking of making a new PSU incorporating all of the ideas, the cost would be built into the product regardless. Do all of the various DC ATX PSUs sold on Ali have these expensive certifications and are they required if sold from the Chinese manufacturer straight to the consumer? 92mm fans do exist, as do semifanless modes - I'm looking for a product that would incorporate as many changes as possible to reduce cable clutter.

I see, so we're approaching this from somewhat different directions. Indeed an 80mm fan on a FlexATX PSU would be lovely (provided it works as intended) to reduce noise, but the space you're using for that can also be used for one or two 2.5" drives, so it's a double edged sword.

I like where you are going with the Pico to ATX 24 (PAX24?) adapter, I guess I'm just trying to spit ball different ways of reducing cable clutter without going that route. If you were going to introduce the perfect SFF SFX or FlexATX PSU, what would it do differently?

Which is good as the first idea isn't always the best one. I think moving part of the 3.3V and 5V generation to a Pico might be worth it, but turning this contraption on is quite a challange already. I did something like that with a thin mITX board, but you need a microcontroller for that.

Good question. I think the SSP-300SUG is quite close to being the perfect FlexATX PSU to me, but I would like it to be a little bit more powerful and have actual modular connectors. And be black, not silver.
The problem with modular connectors is that there's very little space to put them.

Another idea sprung to mind:

What if we used an ATX cable with thicker wires, but fewer that feather out on the connector? So just one thick wire for 12V, one for 5V and so on, and on each end of the cable, the pins that belong together would be interconnected with thinner wires. That way, we can allow for the same performance, less wires and 100% compatibility to all current boards and PSUs while reducing the number of cables to just 10 instead of 24.
 

Ceros_X

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Mar 8, 2016
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Do you have a link?
Does it really save vertical space, though? The ATX cable can always be bent so that it's not taller than the rear audio ports. I'm having a hard time finding a situation where this adapter would actually make cabling easier. I understand that you have to bend it less, but you'll have to bend the cable anyway and it's not going to change how thick it's going to be.

These are what I came up with:
moddiy.com (black)
FrozenCPU (UV green)
Amazon (clear, ugh)

If the PSU's modular port and the mother board where arrange to be in a straight line it would remove the need to calculate cable curve radius because the pins would account for the different lengths of front pin vs back pin rows. Instead it would look to be a straight, mostly flat run. If there was a cable run behind the motherboard tray I imagine it would make for a cleaner looking install as well. Perhaps it looks different in my mind's eye vs how it would turn out :D

Some dude on OCN's forum talking about making a flexible version here

I see, so we're approaching this from somewhat different directions. Indeed an 80mm fan on a FlexATX PSU would be lovely (provided it works as intended) to reduce noise, but the space you're using for that can also be used for one or two 2.5" drives, so it's a double edged sword.
I don't mean putting one on top of a FlexAtx, I mean redesigning the layout so that the internal components aren't as as high as usual and removing the 40mm fan area and replacing it with components and instead mounting the 80mm inside with that as the sole source of ventilation (maybe have more vent holes, don't know what that would do interference wise..). The FlexATX would be totally the same form factor as usual, just rearranged so that the components are short enough in one area to allow an 80mm fan.





Another idea sprung to mind:

What if we used an ATX cable with thicker wires, but fewer that feather out on the connector? So just one thick wire for 12V, one for 5V and so on, and on each end of the cable, the pins that belong together would be interconnected with thinner wires. That way, we can allow for the same performance, less wires and 100% compatibility to all current boards and PSUs while reducing the number of cables to just 10 instead of 24.

I came across this while searching for right angle connectors - would this be helpful to your goal? Amazon.com 24 pin to 10 breakout circuit board
 

BirdofPrey

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Sep 3, 2015
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Well, as far as an a system that works with existing PSUs, what you would want is something like a PicoPSU that not only takes +12VDC and COM but also passes the +5VSB, PS_ON# (controlling both the primary PSU and the one on the ATX connector) and PWR_OK (possibly unnecessary )lines back to a regular PSU (A modular PSU would work best for that, obviously) so that the motherboard can continue to receive standby power as well as monitor and power cycle the PSU. The motherboard DC_DC PSU only needs enough wattage for the motherboard including the EPS connector, while peripherals can still be powered from the main PSU.

if you were to make a new PSU, the best way would likely to be to retain the same DC_DC PSU housed on the ATX connector but increase the power output to be able to supply peripherals as well and change the +5VDC standby to +12VDC; then the AC_DC PSU only needs to provide +12VDC power much like a power brick connected to a regular PicoPSU, but can actually be sensed and power cycled by the motherboard. Unlike a PicoPSU type system, you would be more easily able to properly power large users like GPUs since the AC_DC PSU is the main limitation, and can be turned off by the system.



As far as actual new standards go where both manufacturers and end users are concerned, there is a prior example of how to manage the transition. When ATX first came out, motherboard manufacturers started to make AT motherboards that could accept the new ATX power supplies (and even control them like an ATX board would) while PSU manufacturers made PSU that provided both AT and ATX power connectors.

That sort of situation would work for a redesign motherboard power connector and transition to the motherboard for supplying +3.3VDC and +5VDC
 
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iFreilicht

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These are what I came up with:
moddiy.com (black)
FrozenCPU (UV green)
Amazon (clear, ugh)

If the PSU's modular port and the mother board where arrange to be in a straight line it would remove the need to calculate cable curve radius because the pins would account for the different lengths of front pin vs back pin rows. Instead it would look to be a straight, mostly flat run. If there was a cable run behind the motherboard tray I imagine it would make for a cleaner looking install as well. Perhaps it looks different in my mind's eye vs how it would turn out :D

Some dude on OCN's forum talking about making a flexible version here

Those are just the sockets themselves, you'd have to solder one of them to the mainboard directly, replacing the vertical one that's on there already.

I know that build (you can see a few of my comments in it), but I think that adapter makes little sense at all. It uses the exact same connector that the normal ATX cable uses and an additional socket, so you're basically increasing the amount of space the cable uses. I guess it's nice that you don'd have to bend the cable yourself, but ultimately, it's not really reducing cable clutter.

I don't mean putting one on top of a FlexAtx, I mean redesigning the layout so that the internal components aren't as as high as usual and removing the 40mm fan area and replacing it with components and instead mounting the 80mm inside with that as the sole source of ventilation (maybe have more vent holes, don't know what that would do interference wise..). The FlexATX would be totally the same form factor as usual, just rearranged so that the components are short enough in one area to allow an 80mm fan.

Now I get you! That would be awesome, and I really wish we'll see something like this someday, but that means it's a completely new design, so you'd have to be a reputable company already just to get a manufacturer started on evaluating whether something like that could work. Except if you could convince them that it would sell like hot cakes.

I came across this while searching for right angle connectors - would this be helpful to your goal? Amazon.com 24 pin to 10 breakout circuit board

Not really, I already know what such a cable would look like. But it's certainly related.

Well, as far as an a system that works with existing PSUs, what you would want is something like a PicoPSU that not only takes +12VDC and COM but also passes the +5VSB, PS_ON# (controlling both the primary PSU and the one on the ATX connector) and PWR_OK (possibly unnecessary )lines back to a regular PSU (A modular PSU would work best for that, obviously) so that the motherboard can continue to receive standby power as well as monitor and power cycle the PSU. The motherboard DC_DC PSU only needs enough wattage for the motherboard including the EPS connector, while peripherals can still be powered from the main PSU.

Yes, that's true. PWR_OK wouldn't necessarily have to be passed through as the DCDC PSU already generates that signal itself for its own output. The question is whether the DCDC PSU measures the 12V voltage and sets the PWR_OK signal accordingly. If it does, you don't need an additional signal.

Passing +5VSB and PS_ON# through seems like the simplest way to go. I wonder whether it would be as easy as having those from the main PSU directly connected to the DCDC PSU or whether that could fry one of them. In theory it should work, the PSUs are pulling that signal to TTL high, so something higher than 2.4V and the mainboard pulls it down to TTL low.
The DCDC PSU wouldn't even need to generate +5VSB itself anymore.

I don't know whether putting the EPS connector on the DCDC PSU would be a good idea. On one hand, it only has to pass the 12V through, but for high-end CPUs that would be a lot of current on the 12V input for the DCDC. Personally I'd feel better if the CPU was still powered by the main PSU.
On the other hand, some people building in the S4 mini are powering all their components through a DCDC supply IIRC, so it should certainly be possible. Maybe @Josh | NFC could elaborate what his findings were, he did make a lengthy video about that topic after all.

if you were to make a new PSU, the best way would likely to be to retain the same DC_DC PSU housed on the ATX connector but increase the power output to be able to supply peripherals as well and change the +5VDC standby to +12VDC; then the AC_DC PSU only needs to provide +12VDC power much like a power brick connected to a regular PicoPSU, but can actually be sensed and power cycled by the motherboard. Unlike a PicoPSU type system, you would be more easily able to properly power large users like GPUs since the AC_DC PSU is the main limitation, and can be turned off by the system.

I think the current DCDC PSUs are already strong enough for peripherals, aren't they? The 160-XT is rated for 8A on 3.3V and 5V with forced air ventilation. I wouldn't power an NAS with that, but for two or three 2.5" drives that should be more than sufficient.

Actually, 12V-only PSUs already exist, at least as FlexATX. So this hypothetical DCDC PSU seems like a good first step. If that works reliably, everything else can be phased in later on.

As far as actual new standards go where both manufacturers and end users are concerned, there is a prior example of how to manage the transition. When ATX first came out, motherboard manufacturers started to make AT motherboards that could accept the new ATX power supplies (and even control them like an ATX board would) while PSU manufacturers made PSU that provided both AT and ATX power connectors.

That sort of situation would work for a redesign motherboard power connector and transition to the motherboard for supplying +3.3VDC and +5VDC

I think that could work for our situation as well. First we have a DCDC PSU that allows modular ATX PSUs to have less cable clutter. Then, this PSU would also work for potential 12V-only PSUs so those could be introduced before mainboard manufacturers had to move on. If the mainboard manufacturers started adopting 12V-only first, then at least modular PSUs would already work with that standard.
 

Josh | NFC

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We all know about the 24pin problem. There's this one, unbelieviably bulky cable in our machines that supplies the mainboard with power. It takes up an unnecessary amount of space, is hard to route and in general hinders the advancement of SFF (a little bit).

Some of us already imagined a hypothetical new connector with ~8 pins that would still provide the same functionality and enough performance for ITX boards. But the adoption of something like that would be a chicken-and-egg situation.

But what if there was a different solution?

Some propsed to use thin mITX, but that form factor seems to be pretty much dead for consumers.

With modular SFX(-L) and FlexATX PSUs, what would prevent us from connecting a PicoPSU to an internal PSU like the PicoPSU-160-XT? There is the problem with the #PS_ON signal, but that should be resolvable somehow. If we can deal with that, we would get the advantage of thin mITX with just two wires from PSU to mainboard but could still use high-powered CPUs and any Mainboard on the market. This would also work for mATX boards.

How strong would the Pico have to be anyway? It doesn't regulate the 12V and peripherals might be connected to the main PSU anyway.

Is this a viable idea? Is the ATX24pin cable really that big of a deal to justify something like this?


I'm late to the party but I actually had this idea the other day when working with a dual current system. I think it is totally viable. Not only that, but there are multiple ways of handling this and I am in the process of experimenting with a HDPLEX and Pico 160XT with a single 19v brick.
 

iFreilicht

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I'm late to the party but I actually had this idea the other day when working with a dual current system. I think it is totally viable. Not only that, but there are multiple ways of handling this and I am in the process of experimenting with a HDPLEX and Pico 160XT with a single 19v brick.

Great minds think alike, huh? ;)

What would that setup look like? External 19V Brick -> HDPLEX -> Pico & EPS & PEG? Make sure to post the results of your experiments!
 

EdZ

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One downside of consolidating all the 12V mobo supply onto one connector is that you start to need much thicket gauge wire to carry sufficient current without excessive resistive losses (and heating). You can gain some of that flexibility back by using multiple thinner wires in a bundle, but then you've got something that resembles the existing ATX bundle you started with.

One idea to at least relocate cable clutter is to use a power backplane. Add a PCB with some nice thick copper layers behind the motherboard. Add mezzanine-style power connectors to the top of this board and the underside of the motherboard. Have one edge of the board (like the right/opposite I'O panel edge) protrude to accept incoming cables from the PSU, or a direct mating connector (e.g. card-edge) depending on case geometry. Depending on component height, 12V - 3.3V/5V step-down circuitry could even be contained on this board to relieve the PSU of that job.
An advantage of this setup is that in addition to the mezzanine power connectors on the rear of the board, traditional connectors could sit on top for 'backward compatibility' with regular cabled PSUs. And if the mezzanine connectors were shallower than 6.5mm, the motherboard would be compatible with all ATX compliant cases (fitting in the standoff area). A disadvantage is the added cost of a power PCB and the connectors, and the potential difficulty of seating a motherboard with the constraint of both getting the I/O panel in place and the underside power connectors aligned, when both are perpendicular to each other.
 

Josh | NFC

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Great minds think alike, huh? ;)

What would that setup look like? External 19V Brick -> HDPLEX -> Pico & EPS & PEG? Make sure to post the results of your experiments!


That's how I have it setup. I'm behind due to Computex projects but I'll be able to work on it in a few weeks.

I'm brainstorming on where this can be maximally efficiant. It does use less cables but with a custom modded cable set seems to generate less heat and still looks OK.
 

iFreilicht

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One downside of consolidating all the 12V mobo supply onto one connector is that you start to need much thicket gauge wire to carry sufficient current without excessive resistive losses (and heating). You can gain some of that flexibility back by using multiple thinner wires in a bundle, but then you've got something that resembles the existing ATX bundle you started with.

One idea to at least relocate cable clutter is to use a power backplane. Add a PCB with some nice thick copper layers behind the motherboard. Add mezzanine-style power connectors to the top of this board and the underside of the motherboard. Have one edge of the board (like the right/opposite I'O panel edge) protrude to accept incoming cables from the PSU, or a direct mating connector (e.g. card-edge) depending on case geometry. Depending on component height, 12V - 3.3V/5V step-down circuitry could even be contained on this board to relieve the PSU of that job.
An advantage of this setup is that in addition to the mezzanine power connectors on the rear of the board, traditional connectors could sit on top for 'backward compatibility' with regular cabled PSUs. And if the mezzanine connectors were shallower than 6.5mm, the motherboard would be compatible with all ATX compliant cases (fitting in the standoff area). A disadvantage is the added cost of a power PCB and the connectors, and the potential difficulty of seating a motherboard with the constraint of both getting the I/O panel in place and the underside power connectors aligned, when both are perpendicular to each other.

Yes, you need more material to make the setup efficient, but even if we used 6 wires for that, we'd still have a much more flexible setup than the current 24pin.
That's an additional argument against including the EPS connectors on that power board.

I don't know how much mainboard use 5V and 3.3V these days, but I'd imagine that most of the power draw is in the 12V area, and mainboards only get 2 pins for that anyway.

The mezzanine connectors are a great idea, and would still be less expensive than using a PicoPSU, I'd imagine. Unfortunately this would also break compatibility with ITX cases that don't have space in that area, so it's not 100% backwards compatible. The M1 is a prominent example.
 

Ceros_X

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I think it is a great idea, I just worry that mfgs not standardizing the m.2 mounts on the underside could make it problematic to design room for that component (depending on size of the PCB)
 

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iFreilicht

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Ah I see. If those are the only two uses, I don't see a reason why the PicoPSU wouldn't be able to easily generate them, motherboards are able to supply 75W over one PCIe slot with just two pins for 12V power on the main connector after all.

Yeah something like that would be a lot simpler regarding the power supply signals and there would be no need for modding of any sort. It would always be running though, even if the PC was turned off, so that's a bit of a downside.
 

Marv21

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The Question is, how much draw is there with the MB turned off. Modern "Schaltnetzteile" are below one watt standby use.
 

iFreilicht

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"Schaltnetzteil" is switching power supply or switched-mode power supply in english.
The PicoPSU would still draw a little bit of power, but that's below 40mA I think. I tested that once but I can't remember. Not sure about the GPU, maybe it could draw power while the rest of the PC is turned off.