Make PSU Modular

Discussion in 'Modding' started by psamathe, Dec 5, 2018 at 7:36 PM.

  1. psamathe

    psamathe Minimal Tinkerer
    Thread Starter

    I'm soon going to start a build in a ZS-A4m so I've been looking at FlexATX PSUs. I'm in Europe so there's less to choose from. Imports from outside of EU will be taxed in addition to the generally more expensive shipping costs. My best choice seems to be the FX350-G. It'll be powering an i5-3570K (at stock settings) and a GeForce GTX 1070 Aero ITX. I have a power meter and I will double check that the system under stress doesn't exceed 350 watts.

    Modding PSU
    Initial disclaimer: I won't be modding this PSU until I'm convinced I won't need the warranty any more. With that said, the PSU has more cables than I need and more length than necessary. I'm thinking of cutting the cables where they leave the PSU and hook each set of cables up to an arbitrary female connector (such as a female 8-pin PCIe connector). I would probably skip modding the ATX cable.

    So to further clarify, there'd be four PCIe female connectors that I could hook into after the mod, one for EPS, one for actual PCIe, one for Molex and one for S-ATA. I hope it goes without saying that they're not interchangable.

    This way I'll make the PSU semi-modular and then I can just make my own set of cables for the PSU (18 AWG) with more optimized lengths that connect to its corresponding PCIe connector.

    Has anyone seen such a PSU mod before? Besides the risk of poor craftmanship on my part is there anything I'm not taking into account here?
    owliwar likes this.
  2. Linked Designs

    Linked Designs Minimal Tinkerer

    I've seen a few threads online about PSUs being modded to become modular. I think the most glaring precaution you should take is understanding the risk of opening up a power supply. People have died from charge built up inside of capacitors, even if you leave it unplug overnight sometimes charges can last for weeks.

    AURMEND Trash Compacter

    I'm currently modding mine, Im soldering in a 10awg wire for every 5* 18awg wires.

    One 10awg wire should be good for 5* 17awg. I will be splitting it before the connector

    Only thing to worry about is the resistance between each connectooc/soldering point
    owliwar and cleveland like this.
  4. psamathe

    psamathe Minimal Tinkerer
    Thread Starter

    I won't open it at all. I'm cutting the cables outside of the PSU.
    NateDawg72 and el01 like this.
  5. BaK

    BaK Cable-Tie Ninja

    I understand the benefit of a modular PSU, but since you already know in what case you are putting it in, why don't you simply cut the cables you need directly at the right lengths?
    That's what I did on my MiniCube build if you want to have a look.

    Do you want the PSU to be modular in order to be futur proof, if you change your case later and want to re-use this PSU?
  6. psamathe

    psamathe Minimal Tinkerer
    Thread Starter

    #6 psamathe, Dec 7, 2018 at 2:29 PM
    Last edited: Dec 7, 2018 at 2:42 PM
    The thought of just cutting the cables at the right length from the beginning never even occurred to me. And yeah, I guess it was because of the implicit assumption that the configuration might change one day and then I would just be able to switch out or add the cable I need if I made it modular to begin with. Also, hooking the cables up to connectors gives a natural solution to sets of cabling that I won't be using at all (such as the molex connectors, what would I do with them if I just cut them off outside of the PSU? (Electrial tape, no thanks. Removing them altogether by cutting them off inside the PSU, it's an option but not something I'd like to do).

    In addition to this the transition would also be a natural way to add sleeving to any cabling. I can do the sleeving any way on the cabling that connects to my modular solution. The alternative is to sleeve the cables all the way into the PSU or just arbitrarily sleeve them as close to the PSU I can. The latter is a look I don't really care for, I'd rather have the sleeving end at a connector.
    owliwar likes this.
  7. owliwar

    owliwar Master of Cramming

    I'm honestly thinking on doing something similar on my TFX psu. mostly because my system deverseves better cables and since it doesnt have 6 pin pci-e I kinda want to try see if that works
  8. alexs

    alexs Efficiency Noob

    A bunch of connectors hanging around would take a lot of space. The result may end up being much less upgrade-proof than expected because of the space required to stuff the connectors. I'm not sure it's any better than just cutting the cables to length.

    Heat-shrink tubing is the usual solution. Let it overhang the end of the cut cable by several mm.

    Cutting individual cables inside the PSU is not always possible. Depends on PSU. It can easily be all or none.

    AURMEND Trash Compacter

    Yeah so with my Enhance 600w PSU is really easy to do. Now the FSP one that I had to return was nearly impossible to modify it. I didn't bother.
  10. BaK

    BaK Cable-Tie Ninja

    As @alexs said volume was also my concern, and its not only one connector, its male and female that are added.

    Cutting the right length will also save you from doing the crimping.
    You remove the extra length in the middle of the cable, insert the heatshrink, solder, apply heat and your done.

    Having said that, maybe you can be inspired by this, or take the easy way and buy it ;)
    It looks like it as been designed especially for the ZS-A4M.

    Or this one, we see better the L metal shape attached to the PSU:
    owliwar likes this.
  11. psamathe

    psamathe Minimal Tinkerer
    Thread Starter

    Yeah. That's why I decided against remaking the ATX, but even then it might take up more space than available. I was planning on cutting the cables at different lengths when I add the connectors so that the connectors doesn't bundle up together but are spaced apart.

    In the worst case scenario I'll just cut the cables to the right length and do the connector solution for Molex only and then sleeve everything into the PSU.

    But that's the fun part! I've been wanting to learn how to do my own cables and sleeving for a while now.
  12. BaK

    BaK Cable-Tie Ninja