500W FlexATX PSU

Discussion in 'Hardware' started by iFreilicht, May 12, 2015.

  1. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    #1 iFreilicht, May 12, 2015
    Last edited: Aug 17, 2017
    Sorry everyone, this project is stalled indefinitely.

    The interest for a PSU like this is too low to create a custom unit at this time.

    However, you can get a stock FSP500-50FSPT from Amazon.us.

    Original Post:


    The FSP500-50FSPT is a short FlexATX PSU rated at 500W power output and 80+ Platinum efficiency, made by FSP.
    As is typical with these PSUs, it is not available in retail stores and doesn't have any connectors for graphics cards. I want to change that, so we need to plan out a custom version of this PSU with FSP or one of their distributors, and then either convince a major retailer to stock that unit or make it available via crowdfunding.

    • Dimensions: 150x81.5x40.5mm
    • Volume: 0.495L
    • Power Rating: 500W
    • Power Density: 1010.1 Watt per Liter
    • Efficiency: rated 80+ Platinum, no further details available yet
    • Rails: +3.3V: 15A, +5V: 18A, +12V: 2x24A
    Specification of the stock unit:
    The unit has a PMBus connection, which can be interesting for very specific projects and server use.
    It is missing the -12V rail, which could be a major problem. Some motherboards check whether -12V is present and refuse to POST without it.


    To convince both FSP and a retailer that this PSU has potential in the consumer market, we need to compile a list of people that are interested in buying one or more units of it.
    For a stock or slightly customised version, the MOQ (minimal order quantity) is 300. This includes a different colour for the case or different connectors and cable lengths.
    For more complicated customisations that require some design work (modularity, adding a -12V rail), the MOQ could be much higher.

    To express your interest in this unit, please answer this poll:
    FSP500-50FSPT Wishlist

    If there are other forums where this could be of interest, please PM me and tell me about them! I'd like to get a good amount of exposure on this thing!
  2. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    #2 iFreilicht, May 12, 2015
    Last edited: Feb 16, 2017
    0. First Post:
    As some of you may know, FSP is now listing the FSP500-50FSPT, a 500W, 80+ Platinum FlexATX PSU on their website!

    That thing has a higher power to volume ratio (>1000W per Liter) and is more efficient than the ST45SF-G, ST60SF-G and the SX500-LG PSUs!

    Breakdown of the features:

    • Dimensions: 150x81.5x40.5mm
    • Volume: 0.495L (ST45: 0.794)
    • Efficiency: rated 80+ Platinum, no further details available yet
    • Rails: +3.3V: 15A, +5V: 18A, +12V: 2x24A

    This PSU will easily power a Titan X and highest end i7s at the same time.

    The minimum order quantity is 300 units, so we'll have to find enough people in order to get this sweet piece of hardware.

    Stock specs can be found here:
    Drawing (please ignore connectors)

    We will be able to choose the connectors and cable lengths ourselves, so ignore those in the drawing.

    These are the preliminary changes we want to make:


    San Ace 109P0412H3013

    This was the best we could find, it has the required CFM for the PSU and is a lot more silent according to the specs. It's unclear yet whether FSP will be willing to replace the stock fan for our unit, though.


    • ATX 24pin
    • Auxiliary CPU 4+4pin
    • 2 * Auxiliary GPU 6+2pin
    • (2 *)2 * SATA Power

    These are open for debate, we may also ditch the two 8pin GPU connectors and go down to one 8pin and one 6pin connector to make sure the rating of the PSU is in compliance with the rating for those connectors.

    We are currently in the phase of assessing interest in this PSU and the Mods have kindly allowed me to discuss every little detail about this here on SFN, so we will be able to link a crowdfunding campaign once that's up.

    For now, I would want to create a list of users that are willing to buy one of these, but I'm not sure how to go about it.
    I could make a google docs sheet for everyone to put their names in, a private excel sheet on my PC where you can get in by messaging me or we just make a list in this thread, which could work out, too. Whaddya think?

    1. Reboot

    Let's try this again! I've grown tired of looking on amazon every week to see whether this get's stocked.

    We have to do this ourselves or it will never happen! So, I redid the first post and took a good amount of time to compile a form that gives me an idea of the interest in the PSU itself and its potential features:

    FSP500-50FSPT Wishlist TEST FORM

    This is a test-form to gather feedback on the way the questions are asked and whether their descriptions are understandable! The results from this form will be wiped when the final version of it goes live!

    Please tell me if you find anything unclear or missing from this form!

    I know that some of this was already discussed, but starting from a blank slate will be very helpful here.

    If there are other forums where this could be of interest, please PM me and tell me about them! I'd like to get a good amount of exposure on this thing!

    2. Final version of Wishlist is up!

    The final version of the poll is up! All results of the test form have been wiped, so even if you filled that out, you'll have to fill this one out, too. Sorry for the inconvenience.

    I changed a few minor things to give me a better idea of what people want and need. Thank you all for participating, together we'll make this huge! Or rather, tiny.

    FSP500-50FSPT Wishlist

    3. Poll closed! Discussion of results, information about shipping.
    Update! Poll closed, shipping costs.

    Results are in, poll is closed. In 12 days, 35 people answered the survey which in total are interested in buying 44 units of the FSP500. Thanks to everyone who participated!

    14 of those will make a custom case, 7 will mod an existing case/barebone, 5 are considering the HutzyXS and 1 is thinking about the Brevis S, 5 are still undecided.

    The average maximum price people were willing to pay is 151,36€ incl. VAT, the average price they considered reasonable was 118,64€ incl. VAT. The absolute maximum one person said they were willing to pay was 266,05€ incl VAT. I don't think it will get that expensive ;)

    More interesting results:


    /r/sffpc is apparently very active and distinct from all the other three forums. I didn't expect as many people to react to my post there. The one "Other" entry is actually from one of their mods who found the poll through modmail. /r/pcmasterrace was a little disappointing, the post there didn't get a lot of attention.


    Less than a quarter are absolutely certain that they don't want to do a fan-mod, so I'll make sure to have that supported as best as possible.


    Pretty clear that people are going for looks here. It's safe to say that modular cables are going to be black at this point. Non-modular depends on FSP.



    These are all pretty clear. The PSU should at least be semi-modular. Most importantly, the SATA and PEG connectors should be modular. If only one of them can be modular, it will probably the PEG connector because there are so many different combinations of connectors and cable length people want to use. In terms of SATA the PSU would then provide one single connector on a short cable so it doesn't get in the way if not needed and is easily expandable by using readily available Y-splitters and IDE adapters.
    Considering how many different devices are planned to be connected via SATA/IDE/Floppy power, I would really like that to be modular, too.

    I guess at this point it is safe to say that modularity for the ATX24pin connector is of very low priority.


    If possible, the PMBus header will be inside the PSU to be used by anyone interested in it. If not, nothing is lost.


    This is currently the biggest unknown. I really need to get reliable data on this issue, so I'll ask Gigabyte and co. about it. If modern motherboards have issues booting without -12V and FSP can't integrate a -12V rail, this project is pretty much dead.

    I know I'm pretty much publicising all my market research here, but if any major OEM wants to piggyback off that, feel free to do so. The goal is to get FlexATX to the masses, not to make any profit.

    On a brighter note, I'm quite certain I've got shipping figured out. All units will be shipped to me first and I'll repackage them and send them on using DHL.

    All shipping options are listed below. Every shipping option will be CO2-neutral according to DHL GoGreen and includes 19% German VAT, which will be refunded.
    • To Germany, insured, with tracking: 5.00€
    • To Europe, uninsured, no tracking: 9.00€
    • To Europe, partially insured (50.00€ value), with tracking: 11.20€
    • To Europe (EU only, "Zone 1"), fully insured, with tracking: 14.00€
    • To Europe (outside EU, "Zone 2"), fully insured, with tracking: 29.00€
    • Worldwide, uninsured, no tracking: 16.00€
    • Worldwide, partially insured (50.00€ value), with tracking: 19.20€
    • Worldwide (Zone 3), fully insured, with tracking: 35.00€
    • Worldwide (Zone 4), fully insured, with tracking: 43.00€
    Zone 1, 2, 3 and 4 are defined by DHL. I can ship absolutely anywhere on the planet, it seems, so that's nice. The problem is that a lot of potential buyers are sitting inside the US, which is in Zone 3 and shipping is thus expensive. There might be a solution to this, but I'm not saying anything until it's certain. The prices above are the absolute maximums, though, I can guarantee that.

    Again, thank you all for your support!

    4. Poll reopened, -12V rail talk.
    Update! Poll reopened, -12V rail talk.

    Poll is reopened as quite a few people wanted to put their name on the list. It'll probably stay like that so we can see how interest accumulates over time.
    Once again, you can find the poll here: FSP500-50FSPT Whishlist

    The question whether your board boots without -12V has been removed.

    Everyone not interested in the technicalities can stop reading now. Thanks for stopping by!

    That's because I've got some bad news on the -12V rail front. I've written mails to ASUS, Gigabyte and ASRock, and the latter where extremely helpful! I sent them a list with a selection of Mainboards that covers pretty much every model from them that one could want to use in a build (including boards with soldered-on CPUs and sockets 1151, 1150, 1155, 2011-3 and FM2+), apart from variants with different chipsets and such.

    They then sent that list directly to the R&D department in Taiwan, who checked the designs of each of them to determine whether they need Pin 14 (aka -12V) present to boot or not. Here are the results:
    • QC500-ITXPH: Required
    • AM1H-ITX: Required
    • Fatal1ty Z170 Gaming-ITX/ac: Required
    • H81M-ITX/Wifi: Not required
    • A68M-ITX: Not required
    • FM2A88X-ITX+: Required
    • H97M-ITX/ac: Not required
    • Z97E-ITX/ac: Required
    • H110M-ITX: Not required
    • H170-ITX/DL: Not required
    • X99E-ITX/ac: Required
    • J3160-ITX: Required
    • C2750D4I: Required
    So as you can see, while some of their boards don't need -12V to boot, a lot of them do, including the very popular X99E-ITX/ac and the Fatal1ty Z170 Gaming-ITX/ac. While ASUS and Gigabyte didn't give me any helpful answers, this data alone is enough to convince me that there is no way around adding a -12V rail to the PSU.

    Now on the bright side, I found the Maxim MAX765, which is a very small DC/DC regulator that is outputting -12V and can be powered by any of the output rails (3.3V, 5V or 12V), so it should be relatively easy to get this integrated into the PSU. I will test this regulator and if it works well, I'll ask FSP whether they can integrate it and how that would change the MOQ.

    Again, a big thank you to ASRock for helping me out here!

    5. PSU sample arrived!
    Update! PSU sample arrived!

    Good news everyone! Today I picked up a package from customs, which was sent to me by the wonderful @ilovelampshade! Nobody is going to be surprised about what was in it, so let's take a look, shall we?

    (This gallery isn't displaying correctly for me. If you've got the same problem, take a look here)

    So, as you can see, the PSU itself is very cleverly designed and really fills every bit of available space with something. Almost. It seems like a -12V rail will be relatively easy to get, but it's not looking that well for modularity. @Hahutzy and I are already talking about what cable lengths would work nicely if none of the harnesses can be made modular.
    I'll look into making changes to the casing as well, this would increase our chances of making the PSU modular and would increase efficiency for the fan. Regarding the fan, the beefy microcontroller makes me hopeful that the fan curve can also be adapted for a perfect balance between temperatures and noise.

    I want to note that I will not be actively working on this project for a few weeks, as I'm having exams that I absolutely need to pass and will be on vacation afterwards. Questions will still be answered, and maybe I can get the ball rolling on a few other things, but only when I am sure I can sacrifice a few hours. Please be patient, active development will be continued on the 10th of September. Thank you for your continued support and understanding!

    6. First functional test, modularity update!
    Update! It lives! Modularity?

    Finally I found the time to get this together! All the components for the -12V rail arrived, thanks to @EdZ, who helped me a great deal with component selection! I tested the circuit a week ago, but now I've made a small EPS12V-to-2xPEG6 adaptor to test it with my GPU and made an actual connection to pin 14 on the ATX connector.


    So I'm running Prime95 and Heaven as I'm typing this, and boy, that unit is a lot quieter than every FlexATX PSU I have ever had, even with the partially blocked exhaust. (Apart from the one I modded to fit an 80mm fan, of course) If you're going for a silent PC, it's not going to be for you, but in idle I can barely hear it, even while it's sitting less than a metre from my head, and when running just Unigine or any Game Benchmark, my dual-fan 970 is a lot louder than the PSU fan.

    The fan also has a very nice sound to it when gaming. No whining, just a pleasant and surprisingly deep whooshing noise. It gets a little whiny when stressing the CPU as well, but I don't have a Killawatt yet, so you/ll have to wait for a tangible load-to-noise test.

    What's interesting and a little annoying is that the fan will spin up at its full RPM when starting the system, which is quite loud. While this let's me know that the fan is far from it's maximum RPM with the short dirty tests I'm throwing at it now, I'll ask FSP to fix this behaviour in the final unit. I assume this is a self-test so the PSU can refuse to start up if the fan is not turning properly, which is nice for IPC uses, but no good in a consumer PSU.

    Most importantly, in comparison to the SSP-300SUG, my setup doesn't crash. The PSU is rock solid and even during heavy testing when the fan spins up a little more than average, it can quickly recover. I'm far from reaching the maximum load on this thing, and that makes it all the better.

    Modularity and cables:

    So the current state on this is as follows:

    There will be no modular connectors on the PSU itself. The poll clearly showed that there are cases where less than 20mm of space will be available in front of the PSU. Most importantly, the Hutzy XS will be quite limited in that area, and it is one of the most popular planned builds that involve this PSU. So even if flush modular connectors were possible (which they aren't), installing the PSU in such cases would be a nightmare or straight out impossible.

    But, to redeem this, the SATA, PEG (GPU) and EPS (CPU) power connectors will be on very short cables, which can be extended with any old extension cable from the store, no need to mod anything or make your own extension. These short cables also allow configurations where devices are sitting very close to the PSU and will use up minimum space for people who don't need them at all.

    The ATX cable will be long enough to support pretty much all configurations but as short as possible to prevent cable clutter in situations where the ATX connector is close to the PSU.

    The current lengths for the cables are:

    SATA/PEG/EPS: 8cm
    ATX: 18cm

    The is the next-best thing to semi-modularity we can get.

    The following connectors will be present on the PSU:

    SATA: 1x or 2x
    PEG: 1x 6+2pin, 1x 6pin
    EPS: 1x 4+4pin
    ATX: 1x 20+4pin

    I'm still a little torn on the SATA connectors. On one hand, more than 40% claimed to be using two SATA-powered devices, but on the other hand even more people will be using one or zero SATA devices. So it seems like having one connector and including a splitter seems like a good middle-of-the-road solution, but maybe there are differing opinions.

    Two 6+2 pin connectors will not be possible, though. The limitations on the power draw are just too tight. It might still be doable if you use an adaptor, but you'll be doing that on your own risk.

    So, that's it for now. Things are looking good, as far as I'm concerned. I will go on vacation on Tuesday, so don't expect any further updates during that time. I'll have internet, though, so I should be able to reply if you've got any questions or concerns. Have a nice day and thank you for reading!

    7. Progress on -12 Rail.
    -12V Progress!

    This might be the most boring schematic I've ever done.


    And the PCB isn't much exciting, either:


    It's a very simple solution with an isolated DC/DC supply and a connector. The PCB is 27.4mm*13.7mm and is only using SMD components, so it can be glued to the side of the ATX24pin connector with double sided tape.

    The DC/DC supply can be one of three possible units from XP Power, Recom Power or CUI Inc which are pin-compatible. Which one will be used in the end will depend on availability and assembly cost. The connector is a 2mm pitch JST PH, which is also available from TE, so mating plugs are easy to source for everyone who wants to customise their cable harness but still needs 12V.

    As you can see, the PCB has a somewhat odd layout for the pins with GND in the middle. This has two reasons. First, it allowed to make the PCB single-sided, which reduces cost a little bit. And second, as we found out, some boards - like the Gigabyte B85N-Phoenix - that "check" the -12V rail on boot can be fooled by just shorting the -12V pin to ground. So if someone wants to try that without modifying the PSU, all they need is to get a matching connector and bridge the GND and -12V pins with some solder. So with this pin layout, it is very easy to see whether Vin is shorted to ground in the process.

    At this point I have to mention two things. First, what I just described is of course not officially supported and you might risk damaging your mainboard. Second, this -12V unit can only serve as a voltage reference, it's output current is about 80mA, which is below the current recommended by the ATX standard. This means that on mainboards with PCI (which still exist), PCI cards (which also still exist) that require -12V will not work and could potentially damage this unit by drawing too much current. I don't know whether there'll be any issue with RS-232 devices, but I think that shouldn't be a problem. Good, we got that covered.

    Now the next step for this thing is to panelise it, generate the gerber files and then ask my manufacturer (the company that makes the PCB) and assembler (that company that puts the components on the PCB) for a quote.

    Luckily, I already did part of that:


    The rest I'll do tomorrow. Thanks for reading!

    8. First version of drawing complete!
    First version of drawing complete!

    Today I've finally completed a first version of the drawing! Link to PDF.
    If anyone finds a mistake or has objections, please tell me! The division of connectors to the 12V rails is not final, everything else seems pretty much fine to me.

    I'll add this to the first post so people can find it easily.

    9. Lookout on price and shipping times.
    Update! Lookout on price and shipping times.

    Finally got an offer from FSP today, and we're getting close. This was not the final revision of the unit, but I don't think any of the changes we still have to make would add to the final price.

    TL;DR: Maximum price should be $130 USD before tax and shipping, maximum time from end of crowdfunding campaign to the last person receiving their unit should be 25 weeks.

    First, the good news. FSP did confirm that they will modify the controllers firmware to prevent the Full-RPM self-test on start up, so it will stay quiet at all times. Additionally, the PSU will be black and that will not increase price nor MOQ, so we're still at 300.

    Now for the bad news. This PSU will not be below $100 USD, which was an important price break for many people in the poll. The offer I got is 87.40€ per unit, which is about $93.13 USD. Additionally, the -12V supply which is included with every unit, which will cost me about 5.12€, or $5.47 USD. Now this is still below the magical 100 buck limit, but I can't sell it for that. I need a little bit of a margin, and crowdfunding platforms take their cut as well. I realise that I can't take the usual 1/2 to 1/3 you have with electronics in this instance, but something between 10%-25% is required, so you should expect the final price to be less than $130 USD.

    Also remember that this is all before tax and shipping and that the cables on the PSU are very short and I don't plan to include any extension cables because everyone's needs will be different. I did a little bit of research what options there are for extension cables, you can find a spreadsheet here. It's open for anyone to edit so you can add interesting stuff in there if you want.

    Hopefully enough people will be interested to still get one to reach the MOQ. I'd really like to give this some exposure so more people know about it, but I don't have review units to give out and putting up ads would cost money which I would have to recoup by increasing the price of the PSU. In theory, to lower MOQ, I could raise the units price and then use the additional funds from that to stock some. In theory, with a 50% margin, I could lower the MOQ to 200. Not sure how people would feel about that, though. Maybe something like Massdrops price-drop model could be used, where the price will be lowered once a certain number of people pre-order the PSU, but I don't think any crowdfunding platform supports that, so I'd either have to turn to Massdrop themselves or implement something like this on my website. Not sure, maybe someone of you have other ideas or feedback on this?

    A word about shipping times: On FSPs part, production will take 10-14 weeks, shipping to me will then take another 5. I don't know how long it takes for kickstarter or indiegogo to release funds to the one who's running the campaign, but only after I payed at least half of the total cost will FSP start production, which is over 15.000€. Let's say it takes them 2 weeks, just to be on the safe side. Then after that, I can start shipping, and at 300 units it will probably take me quite some time, maybe 1-2 weeks if I'm working on that full-time. To make it a little fairer, I can ship the units going outside the EU first because those will take longer, but in total it could still take 4 weeks until they reach everybody.
    The worst case grand total then would be 25 weeks or close to 6 months from the end of the campaign to the last person receiving their unit. So to make it until Christmas with possible delays or problems, the campaign should start in the middle of May. I'll probably run it for 2 to 3 weeks, anything above that makes little sense.

    Finally, I also asked them about the FSP500-50FGGBN, a Gold FlexATX unit that will integrate the -12V rail. First samples are allegedly to be finished in June. I'm still awaiting feedback around that, but because of the lower efficiency, I am less confident about the noise profile on this unit. The FSP500-50FSPT to this day is the highest quality and most power dense FlexATX PSU, and I think that you shouldn't make any compromise with such a vital component. However, price is an important factor for many, so it could well be a "budget" alternative for those who find the Platinum version too expensive.

    Thanks for reading! Sorry about the wall of text.
    ColorZepppelin likes this.
  3. Phuncz

    Phuncz Lord of the Boards
    Moderator SFF Purist Gold Supporter

    300 MOQ for (I'd estimate) a $80 - $100 item is about $24,000 - $30,000 just for the product, without shipping and other costs. It seems wise to use a suitable platform for this like Kickstarter or Indiegogo.
  4. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    Yes that's the ultimate goal, but I don't want to start any sort of campaign before every little detail is set in stone with a distributor.
  5. PlayfulPhoenix

    PlayfulPhoenix Just another human
    Site Staff Chimera Industries SFFLAB

    What cases would work best for a power supply of that form factor?
  6. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    Firstly, it is a good opportunity for modders, who don't care about official support ;)

    Secondly, we'd like to supply an ATX- and SFX-Adapterplate, so you can take advantage of more space for your CPU cooler or for a reservoir.

    Thirdly, I've also made a few concepts for FlexATX cases in the past, and I've finally made one that I feel confident in being able to deliver, just google Freilite Brevis S and you'll find it. That's decoupled from this mass-buy, though.
  7. Aibohphobia

    Aibohphobia aka James
    Chimera Industries

    While I ask that people refrain from spamming links to this site on other forums I don't care about posting links to other forums here.

    Here's the build log for anyone too lazy to look it up :p: http://hardforum.com/showthread.php?t=1862045
  8. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    Little big Update:

    I've been talking to a rep from Sliger (they are an official FSP distributor and everything they do involves SFF of some kind) and he's nothing but awesome!

    First of, he already got FSP to send a sample to him with the stock configuration and ordered a sample fan of the San Ace 109P0412H3013 that we would want in the PSU. He is planning to do the cable mods and fan swap on this unit in-house for testing.
    Also, he said that Sliger could make the adapter plates for us, they would be able to do various finishes and materials and even different combinations of mounting positions, maybe even space for HDD mounting and such, which would be pretty cool.

    Everything below was not said by the rep, these are just my personal thoughts:

    This is freaking amazing! Sliger and this rep in particular have shown to be very enthusiastic about SFF, this is the partner we needed in this holy war! :p I think, if we are lucky, we won't even have to do any sort of crowdfunding on our own, Sliger could just add this PSU to their product catalogue, which would be pretty amazing. :D Maybe a first run would still be crowdfunded to help dampen the initial investment risk, but it wouldn't have to require 300 Units to be sold, just 150 or something like that.
    WillBlackstone likes this.
  9. PlayfulPhoenix

    PlayfulPhoenix Just another human
    Site Staff Chimera Industries SFFLAB

    Glad that you've had progress! (And FWIW, our conversations w/Sliger have been helpful as well. Of the manufacturers we've talked to, they've been the most forthcoming, which is always appreciated)
  10. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    Ok, things seem to be going well, both Sliger and Fortron are cooperative on this. So the only thing that's left to decide on now is how many SATA connectors the PSU should have and how long the cables should be, then we can get a quote on the price.

    For the SATA connectors, I added a poll to the post. I don't suspect anyone really needs more than two, and if they do, there's always the option of using splitters. In theory, one connector on a very short cable could even be enough.

    So, let's talk cables. We need to find out what lengths the different connectors should have, so it would be nice if some of you could draw up their potential setups with this PSU and try to figure out what sort of length you'd need in order for it to work out.

    For a bit of orientation, these are the possible locations for the ATX12V (4pin or 8pin) and 24pin ATX connectors on all currently available 1150 mITX boards:

  11. rawr

    rawr SFF Lingo Aficionado

    If you really need to, you could run your SSD off of a fan header... :p just sayin.
  12. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    I think enough people in this community would consider it if it significantly reduces cable clutter in the case :D

    A few people suggested that we use male MiniFit Jr. connectors as the ones used in modular PSUs on short cables (5-10cm) to make this PSU semi-modular, and I quite like the idea, but I'd say the 24pin ATX connector should stay on a long cable and power for the drives would be supplied via a singular SATA power connector instead of a MiniFit one, because that would save a bit of space and is more convenient for people that just want to mount like one HDD atop the PSU.
  13. Aibohphobia

    Aibohphobia aka James
    Chimera Industries

    The 24-pin is too bulky, I say leave it as a longer cable.
  14. EdZ

    EdZ Virtual Realist
    Gold Supporter

    #14 EdZ, Jun 5, 2015
    Last edited: Jun 5, 2015
    I unfortunately don't have one handy to pull apart and photo, but some of the more recent dell workstations use a custom flexATX-like PSU with a 'card edge' output via a flat piece of PCB rather than cabling, leaving almost the entire rear area for airflow. That probably wouldn't fly for a consumer model with the thing having live power on exposed pads unless it had some extra active switching logic (could be as simple as the connector bridging some non-adjacent pads to confirm seating, pending regulatory requirements), but having a card-edge socket could allow for some very low profile modular outputs, with great modding potential for easily making custom wiring harnesses.

    ::EDIT:: grabbed some quick pics. Looks like Delta is the OEM.
  15. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    That is so effin' cool, I'd really want something like that. But you're right, it's probably not going to fly.
    I already thought about other connector families that have the same current ratings but smaller dimensions, but that would make it harder to make the cables for the PSU yourself as crimp tools and hardware would be harder to obtain than the widely spread MiniFit Jr. :/
  16. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    The polls all overwhelmingly show that two SATA ports are the golden middle, so we'll go with that. (The one here isn't really statistically significant, though) Question is: Should they be very close (10-20mm) to allow for clean stacked HDD configurations? Or should they be more spaced out?

    From what I can tell, 30cm for the ATX 24pin and ATX12V cable, and 20cm for the PEG and SATA connectors seem to cover most use cases. Does anyone think that those are too log or too short? If not, I'll start the drawings for the Fortron guy to ask FSP for an estimate.
  17. EdZ

    EdZ Virtual Realist
    Gold Supporter

    Spaced out. It's relatively easy to crimp on an extra SATA power connector to an existing cable (and chop off any excess if needed) but splicing in a longer cable (or adding an extra extender or splitter) is not nearly as elegant.
  18. iFreilicht

    iFreilicht FlexATX Authority
    Thread Starter

    An idea someone on OCN had was to have the SATA connectors on two separate wires that slightly differ in length so you can place your HDDs however you want and if you want to do a stacked configuration you could tie them together, effectively making one cable. I think that would be a pretty good solution to the problem
  19. Phuncz

    Phuncz Lord of the Boards
    Moderator SFF Purist Gold Supporter

    Modular cables on a modular PSU, now that would be interesting for SFF. Only need one SATA ? Use the standard cable. Need more ? Plug them in the in-line connector ! Need a short one ? It's included in the box man !
  20. PlayfulPhoenix

    PlayfulPhoenix Just another human
    Site Staff Chimera Industries SFFLAB

    That would be a pretty notable feature all it's own. The "why don't they all do this" kind :cool: