Demystifying the Modular PSU (help !)

[Outta_Hwrw]

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[mMontana]

6 minutes ago, JaySonic said:

What are the PCI_E2 & PCI_E4 for ? 

PCIe X1 card slot.

[mariushm]

The AC cable going to power supplies is mostly standardized. 

The most power supplies will use the IEC C13-C14 combo  (C13 - female - on the cable, C14 - male - on the power supply) : https://en.wikipedia.org/wiki/IEC_60320#Appliance_couplers

 

 

Some high wattage power supplies (1300w and up) will use the higher current C19-C20 pairing which has the pins horizontal (and they're thicker) :

 

 

 

The connectors going to motherboard and devices (video card, hard drives etc) are standardized.  But the connectors that plug into the power supply are NOT standardized. Each manufacturer can make up their own standard about how cables connect to the power supply.

Corsair has standardized their cables and pinouts are available online, so companies can make cables for Corsair power supplies.

The newest are Type 3 and Type 4  - but if you look at the pinouts, the difference is only in the 24 pin ATX connector, where one version has more sense wires and a wider connector on the psu case :

type 4 : https://pc-mods.com/blogs/psu-pinout-repository/corsair-psu-type-4-cables-pinout

type 3 : https://pc-mods.com/blogs/psu-pinout-repository/corsair-psu-type-3-cables-pinout

 

Seasonic has also tried to standardize their power supplies to use same cable standard, it's published somewhere on their site or forums, and a list of which models use which version of their cables.

 

Other companies will tend to use same pinout as Corsair or Seasonic even if they don't advertise it but there's no guarantee they'll keep doing it, unless they say it explicitly.

 

The Corsair V850 you chose is probably Type 4, because it has that 18 pin part on the 24 pin atx cable. The Type 3 has only a 14 pin header.

 

 

 

1. There is no industry standard for PSU socket types, either in pin# or labelling

 

Correct. As above, some manufacturers have their own published standards, others don't guarantee they'll keep using same.

 

2. Various cables are not ‘straight through’ configurations. For this reason I should ONLY use the leads that ship with the PSU

 

Yes, or if you know they're the same  - for example a EPS (cpu cable) from Corsair Type 4 psu will be the same as EPS (cpu cable) from Corsair Type 3 psu. But may not be same as a Seasonic psu.

3. The 8-pin PSU outputs can be used for both CPU and GPU power, and the cable plugs are identical on the PSU end.
 

EPS (8 pin cpu) or CPU (4+4)  has  4 12v wires and 4 ground wires. 

PCI-e (8 pin or 6+2)  has 3 12v wires and 5 ground wires.

 

EPS has the 12v on the side with the retention clip, pci-e has the 12v wires on the opposite side :

 

 

Because it's easier, on the power supply side manufacturers tend to have 4 12v pins and 4  ground pins and just connect two wires to a pin in the case of pci-e cables, and leave one 12v pin unused.

 

 

4. On the power delivery end, the 8-pin CPU & GPU cables cannot be mis-identified, as the CPU plug will be a split 6+ 2 configuration.

 

No, the CPU can be 8 pin or 4+4 , pci-e can be 8 pin or 6+2. They are KEYED differently (the shape of the individual pins is different) so unless you really force it in, you should NOT be able to plug a 6+2 pci-e connector into the motherboard EPS header.

5. The power delivery configuration is inverted between the CPU & GPU cables (12v on pins 5-8 vs 12v on pins 1-4

 

Yes, that's how they standardized it, on purpose,

6. I won’t need to do ANYTHING with the SATA PSU outputs or SATA cables, since I will not be installing ant HDD, 2.5”SSD, optical drives etc. (my storage needs will be via M.2 slots)

 

It would still be a good idea to have a chain of sata connectors in the case, just in case you have a visitor with a sata drive or maybe you want to use an optical drive for some reason or something like that, doesn't take much space in a case.

May be needed also for fan controllers.

[seon123]

20 minutes ago, JaySonic said:

3. The 8-pin PSU outputs can be used for both CPU and GPU power, and the cable plugs are identical on the PSU end.

That depends on the PSU. Some are different on the PSU side, some are the same, and Superflower has a funky universal 9 pin connector on the PSU side for all of their cables (except motherboard 24 pin).

23 minutes ago, JaySonic said:

4. On the power delivery end, the 8-pin CPU & GPU cables cannot be mis-identified, as the CPU plug will be a split 6+ 2 configuration.

The CPU 8 pin will often split into 4+4, while the PCIe 8 pin will often split into 6+2.

23 minutes ago, JaySonic said:

5. The power delivery configuration is inverted between the CPU & GPU cables (12v on pins 5-8 vs 12v on pins 1-4

PCIe power connectors only have 3 12V pins. The PCIe 8 pin is essentially the same as the PCIe 6 pin connector, but with two extra pins that are there to indicate to the graphics card that the connector can supply 150W instead of 75W. Just the same as how the 4 small pins on the new 12VHPWR connector are there to indicate how much power it can deliver.

25 minutes ago, JaySonic said:

What are the PCI_E2 & PCI_E4 for ? 

PCIe devices. E.g. a Wi-Fi card

[jaslion]

1 hour ago, JaySonic said:

There is no industry standard for PSU socket types, either in pin# or labelling

 

2. Various cables are not ‘straight through’ configurations. For this reason I should ONLY use the leads that ship with the PSU

3. The 8-pin PSU outputs can be used for both CPU and GPU power, and the cable plugs are identical on the PSU end.

1. No standard

2. ONLY use the cables that came with the psu or were VERIFIED to work with that EXACT MODEL!!!!

3. Not always. The cpu is a 4+4 pin config. The gpu is a 6+2 pin config. These have different max power and some psu's split these. It should be clearly labelled if they do

1 hour ago, JaySonic said:

 

 

1 hour ago, mariushm said:

On the power delivery end, the 8-pin CPU & GPU cables cannot be mis-identified, as the CPU plug will be a split 6+ 2 configuration.

4. The gpu plug is the 6+2 pin. They both deliver different max power and CAN NOT be interchanged

 

1 hour ago, mariushm said:

The power delivery configuration is inverted between the CPU & GPU cables (12v on pins 5-8 vs 12v on pins 1-4

5. It depends some pins are optional even

 

1 hour ago, mariushm said:

I won’t need to do ANYTHING with the SATA PSU outputs or SATA cables, since I will not be installing ant HDD, 2.5”SSD, optical drives etc. (my storage needs will be via M.2 slots)

Depends. Some rgb hubs want a sata or molex power plug

 

 

[Outta_Hwrw]

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[Outta_Hwrw]

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[Outta_Hwrw]

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[jaslion]

7 hours ago, JaySonic said:

I appreciate the confirmation on this. That sounds like a potential catastrophic outcome if using random off-brand cables. II have been considering custom-made sleeved cables, but the same danger applies if the guy/girl assembling the cable sets makes a mistake. For this reason, extension cables seems to be a far better option. 

Get from a well known brand. Like cablemod or similar.

 

Extensions are fine too.

[RevGAM]

On 8/31/2023 at 6:27 PM, JaySonic said:

It sounds (almost) foolproof.

It is, unless the fool decides to change the shapes or use excessive force...