[SOLVED] Is this the right cable for my PSU?

[Vax]

I have a SeaSonic G Series SSR-550RM power supply in my daughter's PC.
It's a pretty old one by now I guess. Bought it in 2016.

Anyway, I tried putting it in my daughter's computer, which now has my old GTX 980 in it. The cable it used to have in my case with my own Corsair PSU does not fit into the PCI slots in the back of the PSU.
I found this cable on Ebay. (Link texted it cause the link is super long cause Ebay is stupid).

Anyway, it claims to be a PCI cable for the SSR-450 and SSR-550 PSUs. So naturally I bought it. It arrived today and it fits perfectly. However, when I turn the PC on, it just shows me this error message(pic from Google cause I'm lazy, but it's the exact same thing)

I've double-checked everything, and it still doesn't seem to work properly. :\
Am I doing something wrong here? Did I get scammed and bought a bogus cable?

 

[Lutfij]

Please don't use cables from another PSU since no two PSU's at least to my knowledge will the exact same pinout unless the brand is using the same OEM.

You might want to look into a custom cable making outfit like Ensourced or Titan rig to help you with a new set of cables, unless you're open to suggestions for sourcing a cable from Ebay which often times is sketchy.

 

[Vax]

unless you're open to suggestions for sourcing a cable from Ebay which often times is sketchy.

I only tried till I discovered that the old cable doesn't fit in the other PSU at all.
I tried buying the cable I linked in my post. It doesn't do anything. It just gives the error message in the pic. The cable works, and fits beautifully in the PSU, but when I turn the PC on, that error message is all I get.

 

[Krotow]

Modular PSU cable pinouts can differ between model lines even for same manufacturer. M12II cables doesn't match with G Series cables even if connectors are the same. You must purchase VGA cables (8 and 6 pin) intended for use with SeaSonic SSR-550RM PSU. eBay has them, just checked.

And this is why you must double check that PC seller give to you all cables, bolts, screws, backplates, drive bay mounts and other accessories that came together with components in particular PC. It will spare time, money and nerves for you later.

 

[DSzymborski]

The pinout issue is a serious-enough one that I wouldn't take any random seller on eBay's word for it what the cable is. How do you know "the cable works?" Did you test with a multimeter?